Monday, 30 March 2020

Some more photos and videos of TaurOs cattle

It is not easy to find information on the TaurOs cattle herds. While doing google search I found a photo of a TaurOs bull in Keent, Netherlands. 
The bull looks much like a Pajuna, but the horns do not fit at all. They are much larger and upright than in Pajuna - maybe it's another cross with Maremmana, or a different type of cross. It is hard to guess based on the looks of the animal alone. Here are some cows from Keent. Based on colour and horn shape they might be Sayaguesa x Maremmana crosses, but could also be anything else. 

I also found two new videos of the herd at Milovice, Czech Republic. This video shows, additionally to the bull that looks a bit like a Texas longhorn, two new bulls (6:48). I don't know if they are descendants of the cows in the herd or if they have been moved to the herd recently. Based on their looks they might have Pajuna in their genes. The other video shows some atmospheric shots. 

Looking at the pictures and videos, horns protruding outwards or having a corkscrew-like shape are very common in TaurOs cattle, additionally to upright Maremmana-like horns. The goal should be horns facing forwards and inwards as in the aurochs. Of the breeds used in the project, Maronesa is the only one that has inwards-facing horns on a regular basis. So the horn shape of TaurOs cattle can be improved by producing a number of good Maronesa crosses with inwards-facing horns and using them as breeding bulls at their numerous breeding sites. Otherwise it might become rather difficult for the project to achieve aurochs-like horn shapes. 

Sunday, 29 March 2020

Two new aurochs drawings

Recently I did some new aurochs drawings, one of them is a reconstruction. 
This is a reconstruction of the 182cm tall Vig specimen, based on this photo. The Vig bull is the largest specimen on display. Its horns are more upright (somewhere between 80 and 90° to the snout) and less curved than usual in bulls. Looking at the reconstruction, a mix of Lidia, Chianina, Camargue and Watussi might be suitable to produce a convincing look-alike for this specimen. In case anyone is wondering where the eel stripe is, it would not be visible from this perspective. 
This is a portrait of a bull that is mainly based on the Sassenberg and Braunschweig bull specimen. 

Tuesday, 24 March 2020

Second-generation Auerrind calf born!

Today the Auerrind project announced that the first second-generation calf has been born. It is a bull and the son of the Chianina x Sayaguesa bull and the Maremmana x Watussi cow. 

It will be very interesting to see it grow up. It is completely open what it will look like as the chance that it has a trait of the four founding breeds is equally 25% for all breeds. 

Sunday, 22 March 2020

Aurochs cow colour schemes

While the colour of aurochs bulls is easy to determine (black or very, very dark brown), there is a larger spectrum for the possible colour of aurochs cows. Historic evidence indicates that there was variation, which is also in accordance with the colour of wildtype-coloured domestic cows. 

I tried to illustrate this variation on with a drawing. It shows an aurochs cow which is based on the Camebridge specimen in four different colours, representing the spectrum which is documented by cave paintings and the report from Schneeberger in Gesner 1602. They mainly differ in the degree of eumelanisation. Eumelanin is black pigment, and in wildtype coloured cattle black hair starts to grow on the sides of the trunk, legs, head and neck and continues to grow up to the top of the body, leaving only a dorsal stripe of a lighter colour. Wildtype coloured cattle can either be fully eumelanised (“bull colour”), not eumelanised at all or somewhere in between, depending on when this process stops.

Top left: This colour scheme is completely reddish brown with a dark eel stripe and dark forelocks, and having no black hair except for the tail tip. This colour scheme is similar to that of banteng cows and found in wildtype-coloured domestic cows (see here for a Taurus cow showing this colour). There are cave paintings which might show this variant. The other colour variants, or actually all wildtype coloured cattle, also have a dark eel stripe but reduced to a very fine line that is not always discernable. 

Top right: This is the “standard” colour scheme. Reddish brown with black or very dark brown head, neck, legs, sides of the trunk and tail tip. This colour is very common in wildtype-coloured domestic cattle and you can see it in this Heck cow. It is also illustrated in cave paintings and therefore was most likely present in wild aurochs. Some wildtype-coloured domestic cattle have dark brown hair instead of reddish brown hair, which can be seen in Maronesa cows or some Heck cows (I know of no cave painting that unambiguously shows this colour but it might have belonged to the natural variation of wild aurochs as well). 

Bottom left: This colour scheme is basically black with a reddish brown colour saddle. This colour variant has been illustrated in cave paintings and is nicely shown by the Taurus cow Lerida

Bottom right: “Bull colour”. Apparently, aurochs cows sometimes also had a colour identical to that of bulls. Cave paintings show a black cow and Schneeberger also reports this. This Taurus cow shows this colour. 

There is a continuum between those colour schemes. They represent a spectrum and all possible colours along this spectrum can be found in wildtype coloured domestic cattle, and probably also the aurochs. Apparently there was less selective pressure on the exact colour of aurochs cows so that we find this variation. 

That means that “breeding-back” has room for variation concerning which cow colours are to be permitted in breeding. Other, lighter, colours like beige or very light brown indicate dilution alleles (f.e. see this Taurus cow) and should be selected out as they are most likely domestic mutations. 

Wednesday, 18 March 2020

When to cull cattle selectively in a wild state?

The ultimate goal of breeding-back is to release the herds into nature, opposing them to natural selection so that they become dedomesticated wild animals after a sufficient amount of time. However, there is the problem that breeding-back herds are not genetically uniform and when artificial selection is stopped, their phenotype becomes increasingly heterogeneous in the starting phase. This is what happened to Heck cattle in Oostvaardersplassen. All possible phenotypes may appear. Therefore there is the question whether selective culling should be applied at the start of the dedomestication phase in order to assist natural selection to stabilize a wild animal-like phenotype and prevent very domestic phenotypes. 

Concerning adaptions necessary for survival, cattle and aurochs probably differ in a similar manner as wild and domestic yak. That means we can assume that in domestic cattle, aspects such as fat storage, digestion, metabolism, endurance and respiration are probably different from aurochs and less adapted for a survival in nature, leading to a higher death rate (this is what we see when comparing domestic to wild yaks), and perhaps this is true for other physiological aspects too. Natural selection prefers those individuals with the better genes for a survival in nature. Not to forget, we have intraspecific selection factors such as sexual selection and combat that will influence the cattle (predators, if present, can be a selection factor as well). These selection factors will prefer those individuals that have a higher chance for winning intraspecific fights and being chosen by mating partners, and therefore have a higher reproductive success. This can be caused by genes influencing behaviour traits and certain morphological traits. Not to forget, both factors are connected. Individuals with a more aware and active behaviour as much as the higher readiness to take risks will have a higher chance of winning fights and thus have a higher reproductive success. These behaviour traits are influenced by the corticosteroid hormones, which also influence morphology and are involved in producing the typical domestic morphology. Some individuals might have behaviour traits that are connected to hormonal levels that would enforce a wildtype like body conformation although they do not look “good” in overall appearance. We would have to acknowledge the fact that nature knows better concerning natural selection. 

What selective culling would do is mainly to remove individuals whose horns have the wrong shape or size or that have the wrong colour. This would, in turn, slow down the process of dedomestication as this could often also eliminate individuals that might have alleles for physiological traits advantageous for survival. We cannot know if an individual that has the wrong colour or small horns has alleles for better fat storage, metabolism or other “invisible” factors crucial for survival, or if it has a more wildtype like behaviour. Thus, selective culling based on such optical factors at the beginning of dedomestication would be counteractive. 
And there is the problem of balancing traits. Most people tend to overemphasize colour because it is the first and strongest impression. Yet it is only regulated by very few genes, while other aspects such as skeletal proportions, body shape and body size have a much more complicated background. For example, the Oostvaardersplassen herd has a bull that has a very aurochs-like morphology in build and shape like no other Heck bull has, it almost looks like a Spanish fighting bull. However, it has a grey colour and upright horns. I, personally, would never cull this individual as a lot of genes are involved in skeletal proportions and morphology but only one allele causes this kind of dilution. But someone else might consider this individual to be one of those with the “undesired traits” because of its grey colour and would cull it. 

Thus, my opinion is that breeding back cattle that have just been released into wilderness should not be culled selectively at all in the first decades. At first, the cattle would have to seize their genetic potential without disturbance by artificial selection in order to get dedomesticated and have a chance of survival that is as high as possible. They would have to have get uniform for the traits enforced by natural and sexual selection as quickly as possible and the result will undoubtedly be aurochs-like due to the regression to the wildtype, as wildtype traits (be it morphological, physiological or anything else) are more beneficial under natural circumstances as the wildtype is a product of nature. Relying on pleiotropic effects might also lead to some surprises just like in the Farm fox experiment, only in the opposite direction. For traits that would take longer to be influenced by natural selection, such as colour variants or horn shape, selective culling could be used after a few decades. But I, personally, would not cull selectively within the first thirty years of dedomestication. 

Saturday, 14 March 2020

Some questions and answers

This post is a kind of Q&A post with questions that I have been asked quite frequently or that simply might be interesting. Note that the answers to the questions represent my personal opinion or interpretations based on the sources that I have.

How many types of European wild horses do you think there were during the Holocene?
The common anecdote of a “forest tarpan” and a “steppe tarpan” is not based on reliable evidence. Rather, genetics suggest that there was a continuum from the Russian steppes to the Pyrenees, and the Iberian peninsular being a separate gene pool. Whether or not there were any morphological differences between these populations or within the continuum is not examined yet. So there is no hard evidence for different geographical horse types. Geologically, however, the populations changed over time according to newest genetic evidence. During the Pleistocene, dun horses were predominant while during the Holocene, black phenotypes became more dominant, which is probably related to the shift from an open to a forested habitat. 

When did the European wild horse die out?
This cannot be ascertained as multiple scenarios are possible. Either the genuine wild populations died out completely and were later replaced by feral horse populations in historic or prehistoric times, or there was a gradual shift by continuous depletion of the genuine wild population and intermixing with feral horses, so that the last free-ranging horses at the end of the 19th century were completely feral horses with no wild genes. It is also possible that they were hybrids or, perhaps less likely, still pure wild horses – there is simply not enough data for it.  

Why is there so much less on wild horses on the Breeding-back blog? 
Because there is much less to say. First of all, it is not certain when predomestic horses really died out in Europe, there is not a single articulated Holocene wild horse skeleton or at least a cranium that can be found anywhere, the true life appearance of wild horses as much as the historic sources are dubious and not to forget that the difference between wild horses and domestic horses is not as large as between aurochs and cattle. 

Your opinion on the word “Tarpan”? 
My opinion is that this word should not be used in order to avoid confusion. It was not a vernacular term for the European wild horse as often claimed, but rather a local term in the Russian steppes for the free-ranging horses, whatever these were (it is possible that they were feral domestic horses, caballine wild horses, caballine wild horses mixed with feral horses, Przewalski’s horses or Przewalski’s horses mixed with feral horses). The word “Tarpan” is also connected to the unsupported hypothesis of a “forest tarpan” and a “steppe tarpan” as much as myths such as the alleged origin of the Konik. It would be better to abandon the term overall, regardless its widespread use, and simply refer to predomestic horses in Europe as exactly that or simply European wild horses. 

What do you think about water buffaloes for Europe nature systems? 
I am aware of the ecological benefits of water buffaloes in the reserves where they have been used due to the turbation of small water bodies they make, but I don’t think that water buffaloes would be inevitably necessary in European ecosystems. The subfossil record does not document it unambiguously, also the evidence in Austria is dubious. However, I do think that water buffaloes that are suited to European climate would do no harm. A crossbreed of European domestic buffaloes and Asiatic wild buffaloes might be the best option for this job.  

Did the Heck brothers good work or not?
There is an extensive article on this question. I think we owe the Heck brothers something for inventing the idea of breeding-back. Without their initiative, there probably would be none of the projects or cattle that we have today. But yes, their work was sloppy to a certain degree and could have been done better with the possibilities back then, f.e. they could have done more precise research on the actual morphology of the aurochs, they could have made a herd book and more strict selection criteria. And of course, claiming their heterogeneous breeding result with its only vague resemblance to the aurochs is a revived aurochs was a-zoological. 

Hybridization with living wild bovines for “breeding-back” yes or no? 
I tend to say “no” to this idea. It would make breeding back results species hybrids, what would make the academic and public acceptance for the breeding back results even more difficult. However, a small-scale project crossing wild yaks with breeding back results could be interesting and might also be beneficial for the survival rate of the cattle during winter, as wild yaks are way better adapted to surviving cold winters than domestic cattle. 

Which cattle breed that is currently not used would you like to see being used in breeding-back? 
Quite a lot: Maltese, Chillingham, Corriente, Florida Cracker, Turano-Mongolian breeds, Camargue and others. They would add diversity to the gene pool, and have many beneficial traits; Camargue and Maltese have a very slender morphology, Corriente look very good in general, Chillingham and Turano-mongolian cattle are very hardy and suited to cold climate. 

Will the aurochs ever return in its original form? 
As the full genome of one British aurochs bull from the early Holocene has been completely resolved, it is possible – one way would be to edit the genome of a cattle individual with CRISPR-Cas9 and replace the domestic alleles with aurochs alleles and let a large domestic surrogate mother carry the aurochs calf. It would be interesting to see how far epigenetics and “junk” DNA will influence the development of the individual. I wrote an article on what to do with a living aurochs. 

Which is the best breeding-back project? 
I think there is no fair way just to pick one project or breed. All the current projects have advantages. For example, the Auerrind project has really good quality founder individuals and is experimenting with interesting combinations. The Tauros Programme has quantity, they gained areas and herds rather quickly and now they have to breed for quality individuals. Taurus cattle has both considerable quantity (about 100 individuals in the Lippeaue and 400 in Hortobagy alone) and a lot of high quality individuals that are on the top of what “breeding-back” has achieved so far (Lamarck, Lerida, and other Taurus individuals). It would be most beneficial in my opinion if the three major projects would cooperate, and it seems like this is going to happen some time in some form. One large metapopulation of the best breeding-back cattle available would be an ideal scenario. The resulting cattle could simply be summed up under the umbrella term “breeding-back cattle” or “aurochs-like cattle”. 

Which “breeding-back” herd currently has the best animals? 
In my opinion, definitely the Lippeaue Taurus cattle herd in Soest, Germany. Not because it is the herd that I know best but simply it has a lot of quality animals to offer which have not been surpassed or equalled in other herds yet – Lamarck, Lerida, 42 623, Loxia, Lambretta and many others. In Hortobagy, Hungary, there might be some individuals of a similar quality but I do not know those herds thoroughly enough. 

Which one do you consider the most aurochs-like breed? 
This is a question that is very hard to answer. It also depends on what level you compare the cattle. But, as all factors of a living organism are interconnected, most cattle that have a less-derived anatomy also have less derived behaviour and survival capacity. Actually I think the Iberian fighting bull, Lidia, is one of the least-derived cattle breeds on this world. It is one of the very few cattle breeds that truly has a wild cattle-like morphology despite being small and often having too short legs. Its morphology and behaviour suggests to me that its “domestication syndrome” is not as intense as in many other breeds. There are people who do not consider it aurochs-like because of its exaggerated aggression level, but the tame and docile nature of other breeds is not aurochs-like either. The aurochs was probably in between. A breed that I also consider very aurochs-like, but not in the same way, is Maronesa. It is the only primitive breed that has a well-pronounced inwards curve in the horns and a flawless colour setting with, most importantly, a well-marked sexual dimorphism. This breed is, however, short-legged (bulls) and of small body size. Corriente is also a very aurochs-like breed overall, but small as well. The Maltese ox is remarkable for being large, long-legged and long-snouted but the horns are meagre. After all, all breeds have their pro’s and con’s, but I would say that these four are on the top of those breeds that I am aware of. Lidia, however, sticks out to me for the overall very primitive appearance and morphology. 

Saying that Maronesa or Lidia, for example, are very aurochs-like, would you expect those breeds also to be genetically closer to the aurochs than derived breeds? 
Yes, I think it would show in the genetics to some degree. But I still think that the aurochs is so far removed from all living domestic cattle that the difference might not be that noticeable. It should not be forgotten that there are eight millennia of domestication, a rather dramatic process concerning the genetic structure, are between aurochs and cattle, regardless of local hybridization. 

Is recreating the aurochs by selective breeding possible? 
As I explained in a number of recent posts (for a summary, go here), I do not think it is possible to recreate the aurochs by selective breeding with modern domestic cattle. Domestic cattle are too remote (both in evolutional and organismic matter) from their wild ancestor, the domestication process was probably too intense and domestic cattle are too derived so that a lot of the original gene material of the wildtype was probably lost during this process that is lasting for eight millennia now. 

Can we call breeding-back results “new aurochs”?
I think that we should not call any cattle “new aurochs”. It is true that aurochs of the 21st century would differ a little bit from those of the 16th century, just as those of the 16th century differed slightly from those of the late Pleistocene, but domestic cattle bred for optical resemblance would still be a huge step apart from all geological and geographical variants of the predomestic wild aurochs. Calling domestic cattle a new aurochs just provokes associations with the overly simplistic negligence of the Heck brothers, who indeed thought they had revived the aurochs just by crossing a couple of cattle breeds. It also gives the wrong impression that whenever a wild animal disappears, we can “breed it back” anytime anyway. 
Only a totally dedomesticated strain of aurochs-like cattle would be something that I would call a postdomestic wildtype, just as the aurochs was the predomestic wildtype, but I would not call them aurochs, as it is zoological consensus that “aurochs” refers to the predomestic wildtype of cattle. 

What do you think on the relationship of the quagga and the “Rau quagga”? 
I covered this issue in this post. To me, the Rau zebras are normal plains zebras that have been selected for a reduced stripe pattern while the quagga apparently was more distinct – although this topic is perhaps understudied. Regardless of whether it was a distinct subspecies, a geographical cline or just a colour variant, the Rau Zebras share only a superficial resemblance with the Quagga due to the reduced stripe pattern. While the reduction of stripe pattern in Rau zebras is impressive, it is not completely identical to that of the Quagga, and on a genetic basis, the Rau zebras have nothing to do with the Quagga. In the same way Burchell’s zebras would not suddenly become Grant’s zebras when bred for a more extreme stripe pattern, or Timber wolves would not end up as polar wolves when bred for an exclusively white phenotype. Therefore, I think the Rau zebras should not be called “Rau quaggas” as they are not any more related to the quagga in any sense than other Burchell’s zebras. 

If I would do a breeding project, what would it be like? 
I have so many ideas. For once, I would like to try the combination Maronesa x Chianina/Maltese and supplement it cautiously with few doses of Watussi for horn volume. Or, in order to increase genetic diversity in “breeding-back” start a project working with breeds never used in “breeding-back” before, also including Turano-Mongolian breeds (see this post) or Chillingham cattle and Corriente.. It would also be interesting to breed a herd of the best Lidia individuals which resemble the aurochs to a large extent, and supplying them with breeds that add size (f.e. Chianina, Maltese) and horn volume (Watussi, for example). 
Very tempting to me is the idea to take herd of good “breeding-back” results and select them for wildtype-like behaviour (shyness, low agreeableness, more extreme fight/flight reaction) and to see if the morphology also reverts back to a more wildtype-like condition (this idea would be a reverse experiment the Farm fox experiment and has been introduced in this post). 
Also, it has been an idea of mine to breed an aurochs-like zebu herd (see here). 
Selective breeding with horses for a strong stripe pattern would be to see how far selective breeding can drive the stripe pattern in horses would be interesting as well. 
Apart from “breeding-back” herds, what I would really like is to carry out a project that creates a large and healthy wisent herd that was supplemented by cautious hybridization/introgression from American bison as described in this post. 

If I would want to start a breeding herd now, which where would I take the cattle from? 
I would take some good individuals from the Lippeaue plus perhaps some good and promising Auerrind crosses, and would maybe add one or two individuals from breeds not yet used in breeding back, such as Chillingham or Corriente. This is the composition I would take if I want a larger breeding-back herd. If I’d like to breed on a smaller basis for a line focusing on quality only, I would simply take some good Lippeaue Taurus cattle and try to breed them for maximum quality.

If one extinct species could be reconstructed with genetic methods, which one would be of your preference?
Most resources are concentrating on the woolly mammoth at the moment, and I think this is a good choice – the woolly mammoth is spectacular, popular and important enough to be the first extinct species brought back to life. It would also be my whish that the Tasmanian tiger or moas could be recreated, although this is probably impossible due to the lack of genetic information and suitable surrogate animals. And of course, genetically recreated aurochs would also be very delightful. 

Which one is the most wild horse-like: Konik, Exmoor, Sorraia, Dülmen or others? 
In my opinion, none of them is particularly close to the European wild horse. In the case of the Dülmen pony, it is evident that the modern population is a mix of mostly northern ponies and the Konik, and there is no evidence that the original population from the medieval times were true wild horses. For the other three breeds, genetic tests never unambiguously showed a special status for any of those breeds, and the breed history for both the Konik and the Sorraia shows that it was bred using rural horses, and it also seems that the modern Exmoor pony is an invention of the 20th century. 
If any of those breeds would indeed descend from one of the last remaining wild horse populations, it would definitely show in the genetics; they would be quite set apart from European domestic horses. Also, their documented breed history evidences otherwise as well. Furthermore, their phenotype does not match up. Most recent genetic evidence suggests that Holocene wild horses were mostly of a black phenotype, while none of those breeds above are of that colour. 

Are zebu and taurine cattle different species? 
I think there is definitely no good reason to classify zebuine cattle and taurine cattle as separate species. Surely they are phenotypically far removed from each other, but that is due to artificial selection. Indian and European aurochs, the “natural” state of both clades, were probably not so far removed from each other. There are some gametic processes that show incipient speciation, but subspecies are always incipient species. It is purely a matter of taxonomy that has no relevance for the actual science, but zebuine and taurine cattle and therefore also European and Indian aurochs should be listed as one species in my opinion. 

Heck cattle is a good or bad “breeding-back” breed? 
Heck cattle of course does not meet the initial goal of phenotypically replicating the aurochs, far from it. However, it is an extremely heterogeneous population. While some herds, especially those in zoos and private farms that experienced little selective breeding, are barely useful for breeding back, there are many herds nowadays that are a pretty good basis to work with. Especially regarding the horns, as many of the better Heck cattle have horns that are very good in terms of dimensions and OK in terms of curvature, thanks to lineages such as the Neandertal herd or Walter Frisch’s former herd in Wörth/Steinberg. Not to forget, Heck cattle always have a very good winter coat and are well-suited to Central European climate, which is useful when crossbreeding with southern breeds. 

Was original Europe one big forest or a grassland savannah? 
I believe that as so often, the truth probably was between both extremes. For once, I think the theory that the natural state without any human interference would be forest in Europe is flawed by the fact that we have many indicator species for open land that were present in Europe’s interglacials long before humans arrived, so Europe could not have been just one big forest. Furthermore, bovines were shown to have been pretty common game in the subfossil record, and I do not believe that forest alone would have provided enough suitable space for such large populations to dwell. However, it seems that palinological evidence shows that Europe was not one big grassland, and the faunal utopia of aurochs, wisent, water buffalo, elks, wild horses, Equus hydruntinus and other large game present all over Europe is not backed up by the subfossil evidence either. For example, the European wild horse was much less common in the Holocene than in the Pleistocene, and the record for water buffaloes is dubious. There is solid evidence for wild ass in parts of Austria, but as far as I know only in Austria. Europe probably was not such a large game paradise as Africa, but neither was it a closed canopy forest. Considering that this continent is very multifaceted geologically and geographically, I think it probably was a mosaic of closed, semi-open and open landscapes.