Sunday, 21 October 2018

The real differences between aurochs and cattle

This is another post that might be rather theoretic and goes pretty deep into genetics and other aspects. What I am trying to do here is to give “breeding-back” a scientific backbone. I am not a scientist of course, but my attempt is to go in-depth with the help of the knowledge that I gained in four years of studying biology at the University of Vienna and all the intense literature research I did and discussions and conversations I partook since I started being interested in “breeding-back” in 2011. And actually I think that I gathered a lot of verifiable information in these years. 

Now with this article I am trying to really go deeply into a very important basic matter of “breeding-back”: the differences between aurochs and cattle on a complete, organismic level. It shows that these differences go far beyond differences in horn shape or body size but concern nearly all biological aspects of these animals. This is, in my opinion, very important as it helps to understand what the aurochs, domestic cattle and “breeding-back” results really are. 
This is a subject that I have already covered partly these posts: 
If you feel you are new to this subject, I suggest to have a quick read through these posts. Now it is my aim to write one big, comprehensive synthesis that clearly underlines the wide-ranging differences between aurochs and cattle. 

What is very interesting, and you will hopefully see that very clearly, that all aspects of a living organism are interconnected. Developmental delays or extensions grossly affect the morphology of an animal, which is itself influenced by endocrinology. Endocrinology also affects neurology, which itself affects behaviour. It is not only that factors influence other factors directly via cascades, but some aspects are also connected because they are regulated by the same genes that influence more than one trait. For example, the same genes that affect neurology and behaviour also influence colouration. This phenomenon is called pleiotropy. A living organism is one functional entity. You cannot alter one factor without altering one or several others. This is what happened during domestication and the whole organism has been altered and modified – and not only its morphology and behaviour. And all of these factors are laid down in the genome (except for some aspects that might be influenced by epigenetics, but these are of minor importance here). 

The problem now is that we do not have the wildtype, the aurochs, left alive to study and directly compare to domestic cattle. Only morphological aspects and some of its behaviour are known with certainty, as much as the genome of one individual [15]. The fact that one genome has been resolved only means that we know the sequence of its nucleotids, not that we know the individual role of each single gene in the complex interplay that shapes an organism such as the aurochs. Therefore, to access the differences between aurochs and cattle on organismic basis, we have to take other domestic animals and their respective wildtypes as a comparison. Luckily, domestication seems to work by the same mechanisms and rules in all species that have been domesticated so far [1,2], and some of them, such as the Yak, are more or less closely related and serve as a useful analogue. Thus, we can use these species as a model for the organismic changes from wild to domestic and apply them to aurochs and cattle. 

What is domestication from an evolutionary selective perspective?

Before we go into the organismic that result from domestication, I want to outline what domestication does from an evolutional. In domestication, basically a more or less small population of wild animals is snatched out from the wild and opposed it to relaxed selection on the one hand and massive directive selective pressure on the other hand. The animals are in human custody and therefore less exposed to weather and predation, seasons, are supplied with sufficient amounts of food all year round and the food includes a smaller spectrum than in the wild, they do not have to prey for themselves (in the case of predatory species) and they also have medical care (to a certain degree and not that much in prior millennia). Thus, the requirements on the physiology of the animals (acuteness of senses, endurance, strength, food, robustness, hardiness) are much lower than in the wild. To a certain degree, due to raising animals by hand and the logistics of handling domestic animals, social and parental instincts also become less important and seasonal adaptions loose meaning as well. Another very important aspect is that domestic animals experience far less intraspecific selection as breeding is controlled by humans. There is, mostly, no concurrence between the individuals for breeding success, no sexual selection via female choice or competition, and it is not necessarily the case that the most dominant or most socially competent individuals have the highest number of offspring. Intraspecific selection is a very important evolutionary factor that is lacking almost completely in domestic animals. 
This is where relaxed selection slowly reduces these traits or at least allows these traits to become reduced. Directive selection is, however, actively executed by humans. They bred for certain morphologic and behavioural traits including economic value (milk, meat et cetera), tameness, trainability, and also aesthetics and whatever else requirements human farmers had and have on their animals. New alleles appear as mutations, some of which are considered advantageous by the breeders and become fixated in the population, eliminating their wildtype pendants. Furthermore, genetic drift and the founder effect play a role as well when the population is created and then spread and increased in number, causing a more or less coincidental distribution and disappearance of alleles.
Both relaxed selection and conscious active directive selection as well as genetic drift acted upon domestic animals over millennia and produced animals that differ from their wildtype in looks and behaviour but basically all aspects of the organism (genomic, developmental, neurological, morphological, behavioural, ecological to a certain degree), which is why I write of the organismicdifferences between wildtype and domestic. 

The Domestication syndrome 

The “domestication syndrome” describes the fact that domestication obviously affects all mammals in a similar way with the same organismic changes. These concern, for once, morphology: all domestic mammals show paedomorphy (retention of juvenile characters) in morphology, changes in size, reduction of sexual dimorphism, often hanging ears or modified appendages (changes in horn shape/size and count if present, skin flaps or enlargement of already present appendages), changes in proportion and modifications of coat and coat colour[2,3]. Furthermore, they all have the same behavioural changes which they have primarily been selected for, manifesting in reduced fear response and behavioural paedomorphy (f.e. tail wagging in dogs), agreeableness and trainability2. Domestic animals also all show similar affections of physiological traits and the same reduction of fitness of the genome called the “costs of domestication”[4, 5]. What is also very typical is a loss of seasonal adaptions. Domestic animals tend to mate and reproduce all year round, including cattle, while the reproduction circle of wild animals is adapted to the seasons of the year2

Cattle are a perfect example of the domestication syndrome, at least for traits were we can directly compare them to their wildtype (that is mainly morphology and to some degree behaviour). For all the other aspects, other domestic animals serve as a models for other organismic differences that we can predict with high certainty because it apparently works the same in all domestic mammals. I am going to break down these differences point by point. 

Morphological changes in domestic cattle 

The morphological differences between aurochs and cattle are obvious and have been covered multiple times on this blog (a quick look at the Wikipedia article might teach you the most important facts). In fact, all of these differences are classic “symptoms” of the domestication syndrome: shortened legs and an elongated trunk, in most cases decreased and in some increased body size, reduced sexual dimorphism in body size and colour, reduced skull size and brain volume and paedomorphy in skull shape (shortened face, especially the snout, larger eyes and concave profile in many breeds). Also the "hump" created by the elongated processus spinosi in the shoulder area that is characteristic for the aurochs and other wild bovines, is reduced or completely absent in most breeds. According to the literature, the aurochs skeleton was more robust [6], indicating that the aurochs was more muscular than domestic cattle. The horns have mostly decreased, in some cases increased, in size and developed a lot of different shapes, often loosing the inwards-curve which is typical for horned domestic animals[7]. Some breeds, mostly zebuine, have hanging and/or enlarged ears, skin flaps such as the dewlap, the scrotum and the udder is enlarged in most breeds. The fur sometimes is shorter and not as insulating as to be expected in a wild animal, some breeds, such as highland, have long hair all year round and lack the bilayered fur. Some have curly hair all over the body, some completely lost curly hair. Whether or not hair is curled is regulated by specific genes. A lot of colour mutations evolved, including those causing the typical domestic piebald colour. 
Domestic cattle often have elongated appendages (skin flaps like the dewlap, elongated scrotum). I have been puzzling around what might be the cause of that and I was not able to come up with a developmental, hormonal or neurological connection so I speculate that it might caused by specific genes, perhaps such involving connective tissue formation. In wrinkled dogs, a gene involved in the production of hyaluronic acid synthase 2 causes wrinkling of the skin (also in humans) [14]. 

Affections of development in cattle 

How an organism is going to take shape is determined by when and how much of specific genes is going to be produced, and when they stop. You can produce different morphologies with the same genetic programme via a developmental delay or extension. Domestication usually causes a developmental delay, what means that development stops earlier than in the wildtype. The result is paedomorphy, which is universal among domestic mammals. It is possible that a selection for reduced tameness caused paedomorphy in behaviour (reduced fear response, agreeableness) and by pleiotropic effects and developmental cascades also a paedomorphic morphology. In a sense, domestic cattle are paedomorphic aurochs. In castrated individuals, steers, the removal of the gonads extends some of the developmental pathways as the stopping signal of the gonads is off, and therefore some of the paedomorphic traits are compensated. Steers may have a somewhat more aurochs-like morphology regarding size and proportions – they are more long-legged, long-snouted and also the horns grow longer (some examples here and here). An example for the influence of developmental delay/extension that I investigated myself is horn curvature. I took the Taurus bull Latino’s skull and pushed the rather banana-shaped horn sheaths outwards to the tip of the horn bone, following the curvature – suddenly there was a perfectly aurochs-like horn curvature, the “primigenius spiral” and also the size was right (see here for a sketch). If the horns would have continued to grow significantly (note that the bull was mature) horn curvature and dimensions would have matched those of the aurochs. Thus we can speculate that the actual genes regulating these traits are not different in Latino from those in the aurochs, only the development of the horns stopped earlier in this domestic individual (this, of course, also has consequences for breeding but those will be covered in another post). In the case of drastically deviant horn shapes (such as this one), there might indeed be mutations involving horn curvature. The skull anatomy of cattle is also a classic example for paedomorphy and thus developmental delay. In breeds with a very pronounced paedomorphic skull, the snout is shortened and concave, the nose is rounded and the eyes are enlarged. Actually, in most cattle breeds both the snout and frontal area is shortened (the latter might also be related to horn size), and also the eye sockets of bulls are not as prominent as in aurochs as far as I can tell from domestic bull skulls I have seen to far. I like to call this a “calf face” and developmental delay is very likely to be the cause for these traits. Maybe in extreme examples, such as the bulldog faces of breeds like Cachena and Barrosa, special mutations might be responsible for the condition we see, just the short legs in dachshunds[8], but in most domestic cattle the skull shape might merely be the result of development. 
Most domestic animals, as a result of the developmental delay, also reach sexual maturity faster than their wild counterparts. Domestic cattle are sexually mature about one year faster than extant wild bovines. 
The timing and extent of gene production plays a crucial role, or the crucial role, how an organism is going to develop and it is very likely that extensions or delays, most likely delays, of gene production as a result of selection on tameness has produced a lot of the morphological changes typical of domestic cattle compared to aurochs without necessarily involving extra mutations of the genes that actually regulate the respective body parts (see the horn example). Responsible for developmental delays and extensions are transcription factors that regulate gene activity, which are itself regulated by regulation genes and signal molecules (hormones) produced by the glands of endocrinologic system (these are, again, itself regulated by genes as well). It seems that selection on tameness alone caused a number of drastic changes in the organism in each domestic species that must be laid down in the genome [2], and so in cattle. 

Endocrinologic changes and their consequences 

Two hormone classes seem to play an important role in the domestication of mammals. One of them are corticosteroids which are involved in stress reaction. Domestic animals have a reduced fight/flight reaction, and indeed the corticosteroid level in domesticated foxes dropped by one quarter compared to the control group [2], indicating a causal relationship. We can assume that this similar in other mammal species as well because the types of hormones all have similar effects in mammal physiology, so probably the corticosteroid level of domestic cattle is reduced compared to the aurochs. In breeds with an inherited exaggerated fight/flight reaction, such as the Spanish fighting bull, it might be higher compared to the average of domestic breeds. Doing research on google I discovered something that fascinated me that might be of high relevance: the cushing syndrome in dogs. More precisely, it is called hyperadrenocorticism and describes an over-production of cortisol by the pituitary gland (see here). The symptoms are, among others, lethargy and a morphology that is remarkably similar to domestic cattle: enlarged belly size, reduced muscling, hanging spine (see here and here).   
Another very important class of hormones involved in domestication are thyroid hormones. These hormones have a great impact on the development of many morphological, physiological and also behavioural traits [3]. Thyroid hormones are involved in growth, stress response behaviour, hair growth, adrenal and gonad gland function and pigmentation. Hypothyroidic rats are smaller than normal ones and possess floppy ears [3]. Domestic rats have a smaller thyroid gland than wildtype ones, which is probably linked to increased tameness [3]. Neoteny in amphibians is caused by thyroid hormones as well, and disorders of thyroid hormones cause cretinism in humans. The symptoms of cretinism are shortened extremities, reduced body size and lowered cognitive abilities. This is remarkably similar to what we see in domestic animals. Considering that thyroid hormones are involved in hair production and pigmentation, I think Matthias Scharf’s (from the ABU) suspicion that cattle which have this colour variant that also goes hand in hand with brittle horns and hair have some metabolic or hormonal disorder is perfectly plausible. 

Looking at the effects of both corticosteroids and thyroid hormones on behaviour and morphology, actually I think that we have found the key here, my friends. It seems that selection on behavioural aspects, mainly tameness, changed the hormone system in a way that the aurochs’ skeletal proportions and morphology was changed to what we see in domestic cattle: shortened limbs, reduced size, reduced brain volume and skull size, less muscling and enlarged belly, occasionally a hanging spine. This is perfectly in line with the evidence we get from other animals. 

Neurology and morphology 

The behaviour of animals is not only influenced by the endocrinologic system but of course also the nervous system. Thus, neurological development and neurological genes probably also were altered in selection. These, however, do not only affect behaviour but have a deep impact on the rest of the body. The neural crest is a precursor of many tissue types, influencing f.e. the adrenal gland and pigmentation [1]. For example, melanoblasts (the precursor cells of melanocytes which are responsible for pigmentation) develop in the neural crest and migrate in the target tissue (skin, hair et cetera). Certain alleles on the KIT  locus (called “Star” by Belyaev) cause a delay in this migration during which these cells die, resulting in unpigmented areas in the face (in homozygous foxes at least also body) that we see in most domestic mammals, including cattle (even in humans, where it is called “piebaldism”)[3]. Many of the “colour genes” are actually multifunctional genes that also have a metabolic or neurologic function. For example, mutations of the Dunlocus can cause neuromuscular disorders, such as rolled tails in dogs and pigs caused by myelin degeneration [9]. The Agoutilocus also plays a role in regulation of fat metabolism in the adipocytes[10]. 

Loss of physiological fitness 

Not much is known about the physiology of the aurochs, as there are no living aurochs to study, unfortunately. But there is a comparably close relative of the aurochs that has been domesticated and is still extant in both its wild and domestic form: the yak. This makes it a useful model for the physiological changes that domestic cattle might have undergone during domestication. The differences between wild yak and domestic yak in physiology are considerable. For example, the proportions of g-globin to total globin is higher in the wild yak than in domestic yaks, probably linked to higher stress resistance. Wild yaks also have a higher endurance as the activity of lactate dehydrogenase which prevents muscle fatique is higher in the wild yak. The respiratory metabolism of the wild yak is probably also more efficient as liver, lung, kidney and heart consume less oxygen and the quantity, size and bulk of red blood cells is higher. The wild yak might also be more efficient in digestion as the content of free amino acid in the serum is four times higher than in the domestic yak, and wild yaks keep on increasing in weight during winter, whereas domestic yaks decrease (domestic cattle do so as well) [11]. The death rate in winter is 4% lower in the Datong yak (which is a hybrid breed of domestic and wild yak) [12], so it might be even lower in wild yaks. Wild yaks also have a higher quantity and quality of ejaculate. I think that the physiological differences between aurochs and cattle must be of a very similar manner. The yak was apparently domesticated 4500 years ago [13], and therefore its domestic history is only half as long as in domestic cattle, and basically all of them are landraces and thus not as protected from abiotic and biotic factors as more derived cattle breeds. Therefore I actually expect the physiological differences between aurochs and cattle to be more intense than between wild and domestic yak, at least in the more derived cattle. In pigs domestication also influenced leukocyte count, growth traits, meat character and disease resistance [1], so these factors might also be affected in cattle. In horses, domestication apparently also affected skeletal muscle performance, joints and skeletal articulation, balance, locomotion and the cardiac system [5]. Surely each of these changes reflects the purposes the species was domesticated for, and horses were primarily selected on work purposes. But at least some of these aspects might be affected in domestic cattle as well, especially because the domestic life does not have the same physical requirements as living in the wild as an aurochs. Last but not least, and this is the only case where we have direct evidence from the aurochs genome we have, genes for milk production and quality have been altered by selection [15]. 

Loss of genetic fitness

It is not known whether aurochs and cattle differed in karyotype, or if cattle experienced genomic mutations such as duplications or deletions of entire genes. But what we can say with certainty that the genome must have “suffered” from domestication in a similar manner as in all domestic animals. This includes a loss of genetic diversity and therefore an increase in homozygosity due to the founder effect, genetic drift and numerous bottlenecks [4]. The absence of purifying selection for evolutionary fit traits plus new mutations probably led to an increase of deleterious alleles in the cattle genome (mutation accumulation), because this is what we find in other domesticated organisms [1,4]. This phenomenon is described as the genetic costs of domestication and the deleterious alleles can affect all possible aspects of the organism, including morphology, growth, disease resistance, metabolism, reproduction, neurology and many others [1,4,5]. Conscious inbreeding, especially in the latest two centuries, further intensified the loss of genetic fitness of domestic cattle. This process is still on-going, especially since the more derived breeds are becoming an increasingly important part of the domestic cattle gene pool and absorbing the less derived landraces all over the world. 

Summary.It occurs that there is a long way from an aurochs to modern cattle on organismic basis, despite both being assigned to the same biological species.  Apparently selection on tameness and other characters drastically affected the timing and amount of development of the organism. Developmental delays and alterations of endocrinology such as the corticosteroid and thyroid hormones as a result of selection on behaviour changed the morphology of the aurochs dramatically and produced a phenotype with (mostly) smaller size, shorter legs, paedomorphic skull with reduced brain volume, reduced sexual dimorphism, enlarged belly, reduced muscling and altered horn shape and size. Selection on behaviour also influenced the neural crest development, resulting in affected pigmentation showing in unpigmented areas (piebaldism) in many breeds. Additionally to that, new colour mutations evolved, which might also affect metabolism and neurology. For a number of extreme phenotypes, such as stubby legs and faces, additional new morphological mutations might be responsible. Modifications in behaviour made domestic cattle much more tame, agreeable, trainable and lethargic compared to the aurochs – these changes correlate with the morphological traits because of genetic and hormonal interconnections. As a result of relaxed selection, not only the seasonal adaptions but also the physiological fitness of domestic cattle must have reduced significantly, probably concerning metabolism, digestion, respiration, endurance and stress resistance, which would very likely impact the survival rate under natural conditions as in the case of the yak. From a population genetic/evolutionary perspective, domestication probably reduced the genetic diversity and fitness of the population as a whole compared to the wildtype, which is typical for domestic animals. 
All these changes in sum comprehensively concern the whole organism of the animal. Despite being assigned to the same species and being able to reproduce readily with each other, aurochs and cattle are two completely different types of organisms – wild and domestic. Surely the extent of these differences will vary between breeds, especially between less-derived landraces such as Maronesa or Turano-Mongolian breeds and highly-derived breeds such as the Holstein-Frisian and others, but the differences outlined in this article are very basic and must be universal among domestic cattle as they simply describe the state of being domesticated. I expect variation among breeds only to concern the extentof these changes, not whether the total of these changes is there or not. Furthermore, while it is true that some cattle might be closer to the aurochs than others, I consider it more than likely that all modern domestic cattle are closer to each other than to the aurochs, and that the distance to wild aurochs is quite considerable even in a less-derived breed like Maronesa. 

Consequences for breeding-back 

I think that diagnosing those wide-ranging differences between a wild animal and its domestic counterpart, especially between the aurochs and domestic cattle, has highly relevant implications for the understanding of what “breeding-back” results are. Actually, having researched these dramatic differences that thoroughly makes “the aurochs was larger, had a specific colour and different horns” rapidly loose meaning and almost sound like Kindergarden stuff to me. And judging on a total organismic level it actually it is, in a sense. When I started being interested in the aurochs and “breeding-back” in spring 2011, I looked at wonderfully bred individuals of the Wörth Heck cattle line such as the bull Aretto or the cow Erni and I did not quite understand why those animals should not be considered aurochs. My thought was: the phenotype matches, and the phenotype is a product of the genotype, so why not? Nowadays I am not only aware of the phenotypic differences (size, morphology, behaviour and so on) but I also understand that the differences go far beyond, affect nearly all organismic aspects of the animal and that the genotype definitely would not match in any case. I hope this becomes obvious from this post. Back in the time of the Heck brother’s experiments, for example, these differences where not even known to nearly the same extent. Apart from that, the Heck brothers overlooked many of the morphological differences between aurochs and cattle and failed to properly judge what they bred (for more details, see here). Why should one of their bulls be a resurrected aurochs? Because of similarities in colour and horn shape? From a modern perspective I would say: you cannot be serious, this is not even 2% of the story. So even if breeding manages to fix body size, proportions, horn shape, snout length and other aspects, “breeding-back” results will still remain domestic animals and therefore different animals. The interconnections between morphology, behaviour, development and all the other aspects are so complex and involve so many loci that I do not think that traditional breeding can truly reverse the changes caused by domestication. This is why I mostly write “breeding-back” under quotation marks and strongly reject the term “rebred aurochs”. 
However, some modern projects claim to execute “breeding-back” on a genetic level in order overcome these problems to achieve a more authentic result that might deserve the title “aurochs 2.0”. In the next post, I am going to present my personal take-on to the facts behind this claim. 

Most of the research for this article I did on my own, but I also have to say that some of the references, especially those on the yak physiology, I would have never discovered without the precise and thorough research work of Roberta on the Carnivora Forum Aurochs thread. It helped me great time to complete my body of theories on this subject. Many thanks for that! 


1 D. Wright: The genetic architecture of domestication in animals. 2015. 
2 L. Trut: Early canid domestication: The farm fox experiment. American Scientist. 1999.
3 K. Dobney & G. Larson: Genetics and animal domestication: new windows on an elusive process.2006
4 Moyers et al.: Genetic costs of domestication and improvement. 2017. 
5 Schubert et al.: Prehistoric genomes reveal the genetic foundation and costs of horse domestication. 2014. 
6 W. Frisch: Der Auerochs: Das Europäische Rind. 2010. 
7 Hans-Peter Uerpmann: Der Rückzüchtungs-Auerochse und sein ausgestorbenes Vorbild
8 Kemper, Visscher & Goddard: Genetic architecture of body size in mammals. 2012. 
11 Zhonglin: Development of a new yak breed through utilization of wild yak genetic resource – serial technologies of the development of the Datong yak breed.2004. 
12 Lanzhou Institute of husbandry and pharmaceutical sciences: The 5thinternational conference on yak. 2015. 
13 Lensch, Schley, Zhang: Der Yak (Bos grunniensis) in Zentralasien. 1996. 
15 Orlando, L: First aurochs genome reveals the breeding history of British and European cattle. 2015. 

Thursday, 18 October 2018

Teaser 2

Actually I don't want to post two teasers in a row but the two posts I have in preparation delay a little bit because of the effort I put in it. They should be comprehensive and well-researched. And I decided to switch the sequence. At first I want to post one on

- The organismic differences between aurochs and cattle: A complete comprehensive coverage of all the differences in morphology, physiology, development and genomics that must have been there to deeper understand the different nature of aurochs and cattle and wild and domestic. 

after that, it seems logical to cover 

- Genetics in breeding-back, whether or not genetic breeding-back is possible and if any of the current projects are doing it. 

After that, I want to cover a special dog breed named Tamaskan and its meaning for breeding-back. Also, I want to do a short post on the evolution taking place in Oostvaardersplassen. And, something I did some months ago and want to finally present to the public is 

- A volumetric weight calculation for a male aurochs based on a model. 

Furthermore, I want to self-interview me in a post on some all possible aspects of breeding-back that have been covered on my blog so far. 

And after having done all that, I want to do one comprehensive and handy overview over all the long and important posts I did during the last five years of blogging on breeding-back. 

As you see, I am incredible motivated at the moment and I hope you stay tuned! 

Tuesday, 9 October 2018

Picture of the day: Indian aurochs with hump

I am going to start with doing pictures of the day, considering that I have so much material but so little time to put them into practice properly. So for now, a picture of the day. 

A while ago I did another post on the Indian aurochs, Bos primigenius namadicus. It also includes a new life restoration. In the post, I go over my anatomical speculations point by point. I have not yet considered the fleshy zebuine hump a probable wildtype trait of the Indian aurochs subspecies because it was not possible to identify any functional purpose for the hump (which is, in fact, a hypertrophied Musculus rhomboideus) in the literature yet. So I did not consider it a probable wildtype trait as it is apparently unfunctional. However, one of my readers pointed out to me that it might have display function. 
This idea is actually not that implausible. First off, Bantengs and Gaurs both rely more on display than combat fight than cattle do and as a consequence, they have a shorter and higher profile with high processus spinosi that are not muscled all the way up as in cattle. Also, their horns are more upright instead of fowards-facing as in the wildtype of cattle, the aurochs. Now the Indian aurochs has proportionally way larger and more wide-ranging horns than the European subspecies, which I suspect are less functional than smaller and more compact horns in combat. This might be a hint that the Indian aurochs relied slightly more on display than the European one. The zebuine hump definitely increases the height of the profile of the animal, as do the elongated processus spinosi in Banteng and Gaur. So perhaps the zebuine hump might indeed qualify as a possible wildtype trait, although this is pure speculation. 
And I could not hesitate to illustrate this idea: 
Most likely only contemporaneous art might resolve the question whether the Indian aurochs had this trait or not. 

I feel that my interest in the Indian clade of the aurochs and in zebuine cattle is increasing. Actually I plan to do more research on zebuine cattle, and maybe also do a zebu series on my blog. Lots of research to do, and so little time alas, so please stay tuned. 

Friday, 5 October 2018

Teaser: genetics and breeding back

At the moment I am extremely busy but also extremely motivated to write some more in-depth posts. I have two blogposts in preparation: 

- one covering theoretical assumptions on aurochs genes present in living cattle plus what current breeding-back projects are doing in this respect
- one covering the organismic differences between aurochs and cattle that must be there based on comparisons with other domesticated species 

I think both posts would cover some important aspects that should be discussed in the modern breeding-back world. 

I can't promise when I am done with the posts, probably during the following weeks or so. Please stay tuned! 

Saturday, 8 September 2018

New video of the Tauros cattle in Milovice, Czech Republic

The EuropeanWildlife video channel on youtube released a new video of the Tauros herd in Milovice, Czech Republic. Back in 2015, when the herd was released there, the cattle looked like that

This is what they look like now: 
I like the bull. At first glance, when I discovered the thumbnail of the video, I thought it was a Texas longhorn bull. Colour, face and horn shape somehow fit, and the horns are quite large, about the size of that of a Maremmana bull. It was already recognizable when the bull was young that its horns are going to be large because it had massive horn bases. The body is, in my opinion, similar to some Taurus bulls and absolutely OK, and I like the skull shape - it is elongate, with a slightly convex profile and thus quite aurochs-like. It has a faint saddle, but I won't nitpick on that. All in all, the bull reminds me of Taurus bulls except for the "Texan" horn shape. 
The cow at 0:35 has mighty horns as well. It has a silvery tint in its coat colour and white spots on the belly, so I suspect it could be influenced from the Sayaguesa x Tudanca crossbreeds the Tauros Programme has. There is another cow visible in the video, f.e. 5:30, that looks very Sayaguesa-like and is thus quite good in my opinion. 

Saturday, 1 September 2018

Auerrind update #3

The Auerrind project is really progressing quickly at the moment; now, Claus Kropp has announced that three young bulls have been moved to another new conservation area named Senne und Teutoburger Wald in Germany. The three young bulls are the Sayaguesa x Chianina and the two young Sayaguesa x Hungarian Grey bulls. 
Sayaguesa x Chianina (left) plus two Sayaguesa x Hungarian Grey young bulls (©
The half-Chianina bull is already recognizably larger than the half-Hungarian Grey bulls - this can also mean that it just grows faster, but considering that Chianina are a few decimeters larger than Hungarian Grey on average it is likely that it will remain taller than the others. I think its coat looks like it is about to show its final colour. What is interesting is that Sayaguesa x Chianina bulls can show the full spectrum of an almost white colour to a perfect aurochs colour (this bull seems to be somewhere in between), what is unexpected since both breeds are stable in colour alleles so that F1 cross should actually be more or less uniform. I expect the Sayaguesa x Chianina to grow pretty large and have a long-legged, well-shaped body. It is interesting that the half-Hungarian Grey bulls have a perfect or nearly perfect aurochs colour expressed. I am curious on what their horns will be like as regards to shape and size. 

If someone would ask me what I would breed the Sayaguesa x Chianina to, my answer is clear: females of the same combination, as true F2 Sayaguesa x Chianina has the potential for really large, well-shaped and well-proportioned animals with the right colour and a good horn curvature (so almost the complete package) that is at least a bit stable. Another interesting option would be (Sayaguesa x Chianina) x (Sayaguesa x Watussi), but there is no cow of the latter combination yet. 

I will keep you updated with the recent developments of the Auerrind project. 

Tuesday, 28 August 2018

Tauros cattle moved the Auerrind project in Lorsch

It has just been announced on the blog of the Auerrind project that a number of cattle from the Tauros Project have been moved to the Auerrind project in Lorsch, Germany. In total, eight animals have been moved to Lorsch: 
- 1 young Maremmana bull 
- 1 young Pajuna bull + 1 Pajuna cow 
- 5 cross cows 

Maremmana bull ©
Maremmana bull + Sayaguesa x Watussi cross bull ©
The Maremmana bull is almost two years old and measures 160cm already. It will surely grow some more centimetres and maybe reach 170cm. The body looks rather elegant, but bulls get more massive after the age of 3. The bull is to cover the three Sayaguesa cows next year. For now, it grazes in an own bull herd at Felix Hohmeyer's farm, together with the young Sayaguesa x Watussi bull. It has a flawless aurochs colour but a rather Watussi-like appearance; I am curious how its horn shape is going to develop and how large they are going to be. But even if it is going to look like a black Watussi, it is not its actual looks but its genetic potential it bears that count; bred into a Sayaguesa cow it could still produce a very good result. 
Pajuna cow ©
Pajuna bull ©
The breed Pajuna is going to be incorporated into the Auerrind project. Next year both individuals will be bred to each other in order to have more individuals of the breed. What is interesting is that the bull is black with no saddle - I have not seen this in a Pajuna before. I like the deer-like slenderness of the individuals. They have no plan yet on how to crossbreed Pajuna with. The question is not easy for a two-breed-combination as Pajuna is both a small-sized and small-horned breed. Pajuna x Chianina would probably end up with a good size and well-built body and a correct colour, but it would lack horn size. Pajuna x Watussi would lack body size on the other hand. However, I think they could try the combination Maremmana x Pajuna (a combination already produced by the Tauros Programme, resulting bull here and perhaps also this one). The horn shape could end up unsatisfying as both breeds lack a prominent inwards curve, so Sayaguesa could be added to the mix. 
Pajuna cow (left) plus some Tauros crossbreed heifers ©
The Auerrind programm also has a new herd of five Tauros crossbreed heifers. Claus Kropp writes they are probably Maronesa-, Sayaguesa- and Maremmana-influenced, but a genetic test shall reveal their exact identy. A plan how to use them will be made when their identity is known. 

Saturday, 25 August 2018

New Auerrind herd arranged

The Auerrind project has gained a new area for breeding and natural grazing, the reserve Hammer Auen in Groß-Rohrheim, Germany. Two heifers, namely Ambra the Watussi x Maremmana and the Sayaguesa x Grey cattle, have been moved to the area recently and another two individuals are about to follow. Here are some recent photos: 
Grey x Sayaguesa right and Watussi x Maremmana left (©Copyright
Watussi x Maremmana heifer in close-up (©
The Watussi crossbreeds are among the most interesting to me of the Auerrind project so far. I like the somehow tropical appearance of the fur of Ambra (short, shiny and contrast-rich colour). She seems to have a Watussi-like ribcage but the zebuine hump is only very weakly developed to almost invisible and the horns are probably going to be mighty. The colour is perfect (the distribution of the black pigment is slightly zebuine*, but that is nit-picking; it is very interesting to see that this allele(s) seemingly is dominant). I am curious on which bull is going to cover those cows. Thinking about what combination might lead to promising and strategically useful second generation animals, Sayaguesa might be an option. OK, Sayaguesa is always a good option for crosses as the breed has a lot of very useful traits and you can cross almost anything with Sayaguesa and get a more or less good-looking result. The two Sayaguesa bulls of the project are already in use however, so I am curious on what the two individuals that are going to join the heifers are going to be. 

* I noticed that the eumelanin distribution of zebuine breeds slightly differs from that of taurine breeds. In taurine breeds, the fur starts to get darker on the ventral side of the torso (except for the belly) and subsequently becomes darker from bottom to top except for the eel stripe; if that process stops, we see what we call the "colour saddle". In zebuine breeds, it is reverse, the dorsal side of the torso starts to get darker first and in the end a "colour window" becomes encapsulated on the lateral sides of the torso. Compare the colour saddle of a Steppe cattle bull with the lateral colour window of this zebu bull (this is also mentioned in my recent post on the Indian aurochs). You see the latter tendency in Ambra, at least on an older photo, which is not "negative" in any way but interesting. 

I think it is very enjoyable to see that the Auerrind project is gaining areas and expanding their herds that fast; it looks like they are getting enough areas for a lot of interesting crossbreeds quite quickly. 

Sunday, 19 August 2018

A comment to the Tauros Programme's website

The Tauros Programme has a website since 2015 (, and recently I had a thorough read through it. I have read it before of course, but it did not present any new information but rather the usual formulas the project is using for press releases. All in all, the website is not completely clear on all aspects, but what I find confusing or perhaps not completely honest is the section on the breeds they are using - which is what I want to comment with this post. 

First of all, the list of breeds they are using is misleading. If you open the "breeds" button it shows you the following breeds: Boskarin, Limia, Maltese Ox, Maronesa, Maremmana, Maronesa, Pajuna and Sayaguesa. Highland cattle is not mentioned, which is morphologically far removed from the aurochs, but Maltese cattle are included as if they would be part of the programme in any sort. The profiles for the individual breeds are not always entirely honest either. For example, they attribute Maremmana "strong aurochs features like the size, colour setting, thick horns, clear difference between males and females". I would not directly call the Agouti-diluted grey coat colour of Maremmana strongly aurochs-like - other breeds of the project like Pajuna, Limia or Maronesa are far better in this respect. Also regarding the colour differences between the sexes, as most Maremmana bulls have a colour saddle, it is more reduced than in Limia or Maronesa for example. Actually, it is the colour setting of Maronesa that I would call almost perfectly aurochs-like. As for the horn dimensions, it might be true that there are Maremmana individuals, especially bulls, that have impressive horns, those of most individuals are shorter and thinner than in aurochs. Actually, those of many cows of the project are not that long and actually thin - such as the Maremmana cow whose photo is used for the breed profile on the page. There are actually a lot of Heck cows that have more impressive horns than that individual. On the Pajuna profile, they write that "bulls can reach up to 165 cm shoulder height". This is the alleged record (160-165 is always the alleged record for certain breeds, also for Heck cattle), but the website does not mention that most Pajuna individuals are far from large in size; Pajuna is more of a small breed, as the photos from Keent and other breeding locations prove - the Pajuna cows of the project are the same size as the Highland cows. 
By the way, where is Highland cattle on the website? They portray a large and rather aurochs-like breed that is not used in the project (Maltese) instead of mentioning the small and morphologically quite derived Highland that is indeed used. Highland cattle are mentioned in one sentence on the "breeds" page (where they also mention that they only hope to include Maltese in the future):"Furthermore we incidentally use some individuals of breeds very good characteristics such as the Scottish highlander". This sentence is really dishonest. First of all, the project does not "incidentally" use "some individuals" of this breed, but instead uses or used it on large-scale. Judging from the photos, and I have seen quite a lot, Highland cattle and its crossbreeds always make or made up about the half of the individuals in the Dutch Tauros herds. The technique of the Tauros Project was to use Highland cattle as a quantitative base and to phase it out in later generations, which is perfectly legitimate. Buying and importing cattle from other countries is very costly and effortful, so why not using the cold-adapted Highland cattle that were already there as a quantitative base? Why not writing exactly that? Simply claiming it is the incidental use of some individuals is not a honest description of what is actually done. Furthermore, I wonder what those "very good traits" are and if it is such a very good breed, why it did not deserve its own profile on the page. Highland cattle is a small-bodied breed with short legs, a massive body, short paedomorphic face, and all kinds of horn shapes (a number of individuals, though, has an aurochs-like horn curvature). They also have an overlong coat which makes them tend to overheat during summer, causing them to take baths in mud and drown (see the Weideleitfaden of the ABU). The only advantageous trait of its morphology and physiology is its cold-resistance. They once claimed Highland cattle to be "genetically close" to the aurochs, which they do not dare anymore (for my comment on the Nei distance chart, see here). I am also not happy with the sentence "we also don't use breeds such as the Italian Chianina, because there are better alternatives, such as in this case the Maremmana". Really? As regards to size, I won't say that Maremmana is a small breed, and it might be true that single bulls reach 170-180cm at the shoulders, but if you want to breed for large size and have to compensate the small size of other breeds, and want to introduce a breed that is very large, you need a one that is reliably this size, and not occasionally, and Chianina is definitely larger on average and more stable in this respect. I have not heard yet that Maremmana cows of a size of 160-165cm are common yet. Furthermore, the Maremmana bulls chosen for the programme, at least judging from photos and videos, are not much taller than the Pajuna or Highland of the project, and therefore certainly not of large Chianina size class. Introducing a breed in order to increase size when not picking the really large animals does not serve much purpose. An advantage of Maremmana is that it does not introduce the genes for the stubby very small-sized horns of Chianina, but the horns of Chianina are often of a useful curvature while those of Maremmana are not, and since the Pajuna used do have rather small horns as well such genes will be in the Tauros pool anyway. Furthermore, Taurus crossbreeds of the ABU have shown that even 50% or 25% Chianina individuals can have formidable horns (bulls like Luca, Lamarck, cows like Ludovica). The colour of Maremmana is less diluted than that of Chianina as the latter has dilution alleles on a locus additionally to the Agouti locus (where the Maremmana has its dilution alleles too), but these additional dilution alleles (on the Dun locus according to Olson 1996) are semi-dominant and therefore easier to breed out than recessive alleles. Regarding body shape and proportions, it is definitely Chianina that have a more long-legged, tight and slender morphology than Maremmana on average and in its best individuals. Actually, many Maremmana, including the individuals of the Tauros project, are not that slender and do have a large udder. And in fact two of its bulls are rather longish. I, personally, would prefer Chianina anytime over the Maremmana of the Tauros project, but perhaps that is personal taste. However, what slightly upsets me is that they literally write their breed is better than the other breed that is used by two other programmes (Taurus, Auerrind, with proven success in one of them and for the other one future will tell). 
Another sentence that is worth discussing is: "We also don't use Heck cattle apart from a very small group of animals for scientific evaluation only [...]. Using Heck cattle would imply that the negative traits would find there[sic] way in the Tauros population as well". 
OK, it is of course legitimate not to use Heck cattle and to start completely from a new. There is no reason why not doing so, the potential of breed combinations other than Heck cattle is endless within modern day cattle. Also, when crossbreeding it is advantageous when the breeds used for crossing are more or less stable. Heck cattle is not stable, not even more or less stabilized lines such as the former herd of Walter Frisch. So if you pick an individual for its good and large horns, chances are that it also inherits small and less good horns. So not using a unstable breed is understandable. But what exactly are those negative Heck cattle traits the Tauros programme does not want to get its gene pool influenced by? The negative traits found in the Heck cattle pool as a whole include (the way I see it): 
- comparably small body size 
- short-legged body with a massive, domestic body and short faces
- small and thin horns 
- large udders
- wrong horn shapes, f.e. upright, straight or lyre-shaped Steppe cattle-like horns
- diluted coat colour variants, incl. Grey cattle-like colour 
- strongly reduced sexual dimorphism in colour 
- white spots 

The bitter truth is that all of these negative traits are actually already present in the Tauros pool. Pajuna and Highland introduce small size, Highlands have the short-legged massive body and skull of domestic cattle (even more so than Heck cattle), small and thin horns are found in the Pajuna chosen (those of Limia cows are not large either, and those of many of the Maremmana and Boskarin cows of the project do not surpass those of Heck cattle), large udders are found in a couple of individuals of different breeds of the project, Maremmana and Highland introduce unwanted horn shapes facing upwards, outwards or having a lyre-shape, Maremmana introduces the recessive Agouti-dilution found in many Heck cattle, Highland introducess the recessive e allele that disables the production of black pigment, Sayaguesa has a very reduced sexual dimorphism in colour (and quite a lot of crossbreed Tauros cows as far as I can tell) and also introduces the genes for white spots on the belly (not all but some Sayaguesa cows have small white spots on the belly, so does at least one Sayaguesa cow and some of the Sayaguesa x Tudanca cows of the project). Actually Highland introduces a lot of these undesired traits, which might be an explanation why some of the Tauros crossbreeds look a bit Heck cattle-like (see here), which is something that I predicted in 2011 already. Apart from that, I wonder what the "scientific evaluation" is supposed to be. 

This post is not meant to bash the Tauros programme itself. Not at all. Actually I wrote in a lot of posts that I appreciate the project and think it has good potential and that many of its crossbred individuals do look good. Something that I wish from the Tauros programme's PR work is information instead of promo, but now after years I learned that we will only get promo, promo and promo (also it is always the same kind of promo forumulars), so now the only thing I wish is honesty. And those sentences that I quote here are far from honest, as well as almost concealing the big part of Highland in the project but including a portray of Maltese as if it was one of the used breeds. What I also dislike is that they are constantly putting down other projects or breeds (see the Chianina example). I know that the Tauros project probably is constantly trying to maximize founding etc. and therefore its web presence is nothing but promo and tries to communicate why their project is flawless, perfect and the best and "most scientific" of all, but that style of communicating is not honest and also not fair. None of the other projects does that and I also bet that the other projects do not feel the need to. 

Friday, 13 July 2018

Transforming Leo into an aurochs

Some weeks ago, Claus Kropp published a photo of the young Sayaguesa bull Leo on facebook:
Sayaguesa bull Leo © Claus Kropp

Leo is from one of the best, if not the best, Sayaguesa herds that I have seen so far owned by Peter van Genejgen. Body shape, horn shape and skull shape are superb, the colour is good as well. The herd is slightly influenced by Alistana-Sanabresa, resulting in some reddish cows, giving the illusion of improved sexual dichromatism but bulls from the herd may happen to have a colour saddle (see here). For the European aurochs, there is only evidence for solidly black bulls. Leo has a colour saddle too, however, it still is a very beautiful bull and I think among the best Sayaguesa bulls I have seen. See his elongated head on this photo by Claus Kropp. When judging the body shape, keep in mind that it is still a young bull, it continue to gain weight while its skeleton will finish growing at the age of six years.

The beauty of the bull and the photo inspired me to do another photo manipulation. I took the photo and edited it using GIMP, trying to transform it into what I imagine a European aurochs bull to have looked like. Here is the result (as it is based on a photo by Claus Kropp, I asked if it was ok to present it here):
I changed nothing about the proportions, head size or head shape. I think they are pretty aurochs-like in the original already. I enhanced the morphology of the trunk: the hump had to be enlarged, and I gave it a more slender waist in order to achieve a more wild cattle-like morpology. Also I removed the colour saddle, as there is only evidence for black bulls in Europe and I am not convinced that there were European aurochs bulls with a colour saddle (see here). I removed the original horns and painted aurochs horns. I could have also reduced the length of the dewlap, but I was not sure. For comparison, here is an animated GIF composed of the original Sayaguesa bull and the "aurochs":

As you see, Leo is not that far removed from the goal. I am sure that many of his offspring will resemble the aurochs to a large extent by domestic cattle standards.

Thursday, 12 July 2018

Auerrind cattle are taking shape

Claus Kropp from the Auerrind project just published some new current photos of the first-generation Auerrind crosses at Kloster Lorsch, Germany, on facebook. It looks like they are becoming little bulls and cows now, not calves anymore, and start to take their final shape and colouration. All of them are copyright by Claus Kropp, so please do not replicate without permission. 

Maremmana x Watussi 
© Claus Kropp
© Claus Kropp
In the bull, it looks like Maremmana has absorbed almost all of the zebuine traits (at least those not present in Podolian cattle anyway, which are already influenced by zebus), only a slight hint of the zebuine hump seems to have remained. Watussi contributed dominant alleles for the expression of red pigment in the coat. So in the end, the bull might look like a red Maremmana bull with large horns, which would be a pretty interesting sight. A (Maremmana x Watussi) x Sayaguesa might be a combination worth considering, it might end up similar as Sayaguesa x Watussi but with less zebuine influence and a better winter coat. 

Sayaguesa x Chianina 
© Claus Kropp
© Claus Kropp
Both the Auerrind project and the Lippeaue have produced a couple of Sayaguesa x Chianina in sum by now, and it seems that about 50% of the bulls of this combination have a wildtype colouration and 50% have a diluted coat colour. I do not know why. However, it does not matter at all what the phenotype of these F1 look like since both the phenotypically wildtype and the colour-diluted individuals will have both alleles and pass on one of these with a 50/50 probability. So I think that this bull should be used for further breeding in any case. Its offspring will have the potential for a correct, un-diluted wildtype colour, even in a homozygous state (although it not the statistically most likely case). 

Sayaguesa x Hungarian Grey 
This cow seems to develop a slender body, the colour is diluted and the horns will probably end up Steppe cattle-like. Together with a bull of the same combination, a Sayaguesa x Chianina or a pure Sayaguesa it might produce interesting results. 

It also seems that they are giving the combination Chianina x Watussi a try again, which I am very much looking forward to: 
© Claus Kropp
They also published a promo video on a new youtube channel: 

I have to say it is very exciting to watch the Auerrind project progress. They have very, very good founding individuals and are trying interesting and promising combinations. I think they have the potential to produce very aurochs-like individuals in perhaps the second and very likely the third generation already. 

Wednesday, 11 July 2018

B.p. namadicus: bone material + new artworks

I already did a couple of posts on the Indian aurochs, Bos primigenius namadicus, the most comprehensive and up-to-date being this one. At the time of writing that post, the only picture of original material of this enigmatic subspecies I knew was a drawing of one skull. Thanks to a Carnivora Forum member I finally came across photo material of a few specimen. The two upper photos show bulls for certain, I am not sure about the last one.

The skull material

The crania show some very interesting morphological differences to the European subspecies, B. p. primigenius. First of all, the skulls are definitely narrower than European skulls (the upper one might still be within the variation range, though) and most zebus tend to have a very slender face as well. The horns of the known specimen are, as given in the literature, wide-ranging and considerably longer in proportion than the average for European skulls (which had, though, regional and chronological variation).  Considering that many zebuine or zebuine-influenced breeds tend to have large to very large horns, this might be a basal trait – although the huge horns of, for example, Watussi and similar breeds have certainly been enhanced by domestication.
There is also a more precise drawing of the Lydekker skull available on the web, which also shows it in lateral view. At least this skull seems to have the same 60° horn orientation as in the average European aurochs.

New Indian aurochs art

Seeing these photos of original bone material of the Indian aurochs has inspired me to do some new life illustration of this interesting subclade. As explained in the post linked above, there are a few traits that can be said with certainty, some that can be inferred by parsimony and some traits displayed by zebuine cattle might actually be wildtype traits of the Indian aurochs.

Directly proven traits:
- smaller body size, perhaps between 150-160cm for bulls
- proportionally longer, wide-ranging horns

Traits inferred by parsimony:
- a more slanted pelvis than in taurine cattle
- basic aurochs and wild cattle morphology (long legs, athletic body)
- E+ base colour

Zebuine traits that might in fact be wildtype traits:
- longer dewlap than in the European aurochs (functional purpose: thermoregulation)
- zebuine colour modifiers

Putting everything together, here is the result:

The head and horn shape was drawn to match the skull material. I tried to give the face a kind of zebuine appearance. The body shape is the classic aurochs body shape (I do not assume any differences in proportions, hump size or other morphological traits as long there is evidence for). As for the colour, here is were intuition comes into play. Many zebus show white areas between the forelegs, on the dewlap and also the underbelly, which is said to be caused by a “zebuine tipping gene” (it is not specified whether it is an extra locus or just an allele) and also displayed by other bovine species. I like to illustrate my namadicus with this trait. Also, zebus tend to have another form of colour saddle, different from taurine cattle. It is not a true saddle that covers the upper middle part of the torso, but the sides and often merges fluently into the “zebu tipping area”. Many zebuine bulls show this trait, and it might just be a consequence of reduced sexual dimorphism as in taurine bulls, but for this drawing I assumed it to be a wildtype trait. It is pure speculation, but intuitively I think it is not an improbable colouration for a tropical bovine, which tend to be more colourful than boreal ones.
I also did not give it any curly forelocks. Forelocks are well-proven for the European subspecies and the wide majority of taurine bulls and also cows have them, yet no zebuine cattle show curly forelocks. Tropical bovines tend to have skin flaps and long dewlaps for display, while those in temperate climates tend to have hairy ornamentation for thermoregulatory reasons, thus I think it is plausible that Indian aurochs did not posses forelocks but an elongated dewlap instead. In previous posts I ruled out that the zebuine hump has any function, and therefore did not assume its presence for Indian aurochs. However, a Carnivora Forum member pointed out it might have had a display function in the wildtype, just as the enlarged processus spinosi have in Gaur and Banteng. This is very speculative, however, and probably only prehistoric art could provide a clue.

Being motivated by my new Indian aurochs bull portrait, I could not hesitate to do a table of bulls of all three aurochs subspecies along with their domestic descendants.

As there is only evidence for black aurochs bulls in Europe, I gave the primigenius bull a solid black back. However, for the African aurochs, there is evidence from at least two artworks that at least some bulls of this subspecies had a colour saddle (see here). So the colouration of the African bull is not as speculative as that of the Indian bull. It might as well be possible that all three geographical variants had a solid black colour like the European one. As there are no morphological differences between the African and European aurochs noted in the literature, the African and the European aurochs are actually the same drawing, only the colouration is different. The subspecies that sticks out is the Indian one, which is not surprising considering that the lineages of taurine cattle and zebuine cattle, and thus B.p. primigenius and B.p. namadicus, separated 1,7-2 million years ago[1], which is considerably longer than between Przewalski’s and domestic horses, for example. Here is a close-up for the Indian aurochs alone:
I think the drawing does look plausible for the wildtype of a bull like this one down below.

Something interesting that I noticed is that the size difference between all five bovines is not that huge, especially not between the wildtypes and their domestic derivatives. I drew them to the same scale. For the European aurochs, I chose a size of 170cm at the withers, for the African 160cm and for the Indian aurochs 150cm (which is, by the way, the lower size limit for European mainland bulls). The taurine bull has a height of 140cm, the zebu about 135cm. But the size difference does not appear that large. I think the reason for that is that withers height is not the most reliable measure for this comparison, as it is dependent on the size of the hump i.e. the length of the processus spinosi, actually. In very derived taurine bulls and most zebu the height of the spine does not surpass that of the shoulder blade, thus a domestic bull with a withers height of 150cm would have a larger body than an aurochs of the same withers height, especially considering that they are more elongated in build. So what is actually better comparable is the height of the shoulder blade. The question is, how much higher is the actual height of the shoulder blade of aurochs compared to cattle? Is it due to scaling or is the size difference between aurochs and cattle not that large in the end? The best way to evaluate that would be to compare a skeleton of a grown aurochs bull to that of a domestic bull in real next to each other. But considering that heavy bulls of domestic breeds can easily exceed 1000kg living weight while estimations for aurochs bulls are about 700kg  (by Cis van Vuure, I have reasons to believe they might have been actually 100-200kg heavier, but more on that in an upcoming post) it might not be that improbable. Surely, some aurochs individuals truly were huge by cattle standards as there are skulls of European aurochs with a length of more than 90cm.

In any way, I did an animated GIF of a the European aurochs and the taurine bull at the same withers height – it is obvious that the taurine bull has a way larger body due to the low processus spinosi and the elongated trunk. Even the head would have the same size. A taurine bull with a shoulder height of 170cm would have a weight of about 1700-1800kg, which is twice as much as what is estimated for an aurochs bull of that size.
“Breeding-back” with zebus, once again

In all my previous posts on the Indian aurochs, I introduced the idea of “breeding-back” with zebus. India is full of zebu landraces that are not well-known elsewhere but would be suitable for such a project as they have a slender, squarely-built body with long legs and long snouts. These include Kenkatha, Malvi, Ponwar, Haryana, Khilari or the large-horned Gudjerat. Such indigeneous zebus could be crossed with Watussi for the horn size and curvature and miniature zebus for the aurochs-like colour and dichromatism. Both Watussi and miniature zebu have taurine introgression, but as we know from “breeding-back” with taurine cattle, it is impossible to keep the taurus and indicus lineage 100% separated and it is the contributed traits that count, not pedigree. While the morphology and external appearance of the European aurochs is well-known and breeding with its descendants can approach most of its traits rather well, the life appearance of the Indian subspecies is far less well-known and zebus seem to be a bit more removed from their ancestor than taurine cattle. At least, there are no truly overall primitive zebuine breeds. However, breeding with the zebuine cattle listed above can produce a population that resembles namadicus in horn shape and size, proportions, skull shape and probably also colour. Most interesting would be to release them in a reserve and let them live for themselves for a number of generations. Heck cattle in Oostvaardersplassen underwent morphological changes after a mere 30 years of natural reproduction (see here, here or here) and it is likely that these zebu would experience something similar. These changes would be functional and evolutionary advantageous as they are the result of natural selection. Therefore, it would be interesting what happens to the shoulder- and neck region of the cattle. In Oostvaardersplassen, Heck cattle developed a tendency to have a stronger shoulder region including the typical hump of wild bovines with elongated shoulder spines that support larger neck- and shoulder muscles which are needed during combat. In zebuine bulls, the neck muscles seem somewhat weaker which might be a consequence of the fleshy zebuine hump which is caused by a hypertrophied M. rhomboideus. Thus, a bull with a zebuine hump might be in disadvantage compared to such with a wild cattle-like shoulder morphology. If, after a couple of generations, the zebuine hump would indeed disappear and they would develop a wild cattle-like hump like Heck cattle at OVP, it would be a strong hint that the fleshy zebuine hump is an artefact of domestication and was not present in namadicus as it is not functional. If, however, zebus do indeed use it for display, head-to-head combat might play a lesser role in their social life than in taurine cattle, and it might remain. This can only be demonstrated by executing such a zebu dedomestication experiment.

Other posts on the Indian aurochs: 


1 Hiendleder, Lewalski, Janke: Complete mitochondrial genomes of Bos taurus and Bos indicus provide new insights into intraspecies variation, taxonomy and domestication.2008.

Further, for the description of namadicus and africanus in the Literature:
Van Vuure: Retracing the aurochs: history, morphology and ecology of an extinct wild ox. 2005.