Tuesday 30 November 2021

Lions prefer killing piebald cattle

In my dedomestication series from 2015 I speculate on the selective pressures acting upon the genetic structure of feral domestic animals that will eventually turn the feral animals into wild animals adapted to their environment. I made the prognosis that the animals will show a regression towards wildtype traits because these provide a greater evolutionary fitness since they are the product of past natural selection. Colour would be one of the examples. I speculate that predators would influence the colour of the animals, because some variants are well-camouflaged and others are not, such as piebald individuals. This would, after a sufficient amount of generations in the wild, lead to an eradication of alleles producing piebald colours which are typical of domestic animals and to a genetic fixation of non-piebald (wildtype) alleles. 

My dedomestication hypothesis has empirical problems, as there is no feral population of domestic animals in the same habitat as their wildtype under the same ecologic circumstances that has been reproductively isolated for a sufficient amount of time. But recently there was a study that might provide empirical support for some of my prognoses postulated in the dedomestication series. 
The prey behaviour of lions preying on cattle in Botswana has been analyzed in 2020 by Weise et al.. What they found was not only that lions prefer to kill cattle that are easier prey such as hornless individuals (which is not surprising, as hornless cattle have a much harder time defending themselves against predators than horned cattle), but also that piebald cattle have a higher risk of being attacked by lions. Lions seem to prefer piebald cattle over solid coloured cattle [1]. The authors speculate that a piebald colour makes identifying movement easier for the lions, and therefore they are attacked more often than solid coloured cattle [1]. I think that it is also possible that it is simply the fact that piebald patterns stand out more than solid colours, so that these individuals are attacked more often.  
The authors also found that short-horned cattle were preferred over long-horned cattle, which were mostly avoided by the lions. 

These findings are very interesting. In my view, they clearly suggest that at least some wildtype traits (solid colour, long horns) provide a selective advantage over domestic traits (piebald colour, short or no horns). The authors indirectly say the same by pointing out that cattle lost adaptions of the aurochs against predators [1] (this is a generalization that is not actually true, as there are cattle which still have large forwards-facing horns, significant body size, an athletic long-legged stature and wildtype colour et cetera). This implies that in a heterogeneous cattle population, where some individuals have these wildtype traits and others do not, this will lead to an increase in the frequency and eventually the fixation of the wildtype alleles, and therefore a regression towards wildtype traits, when exposed to selective pressure caused by large predators. 
This shows that the selection criteria of "breeding-back" are not pure cosmetics as some critics repeatedly claim, but actually contribute to the survival of the population of the animals once returned into an ecosystem with predators. 

Literature 

[1] Weise et al.: Lions Panthera leo prefer killing certain cattle Bos taurus types. 2020. 

11 comments:

  1. Very interesting, this study supports the idea of an active "breeding back" as a booster tool along with natural selection, it could make rewilding faster.
    I remember reading an article on wolfs preferring to prey on piebald hybrid pigs over wild, in italian Apennines.

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  2. I see that the Weise et al. paper includes some Daniel Foidl artwork!

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  3. I think that cattle are short legs because is adapted to be scared away not to flight. Doñana wild cattle have long legs because it was used as game trophy the same Autalian wild cattle is adapted to flight. More lidia have short legs because is adapted to charge, not to flight.

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  4. https://images.app.goo.gl/VRTVWj9WxJYyqKZa8
    Doñana wild cattle

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  5. I think the key thing to take away from this is that Lions are very capable of hunting at night (87% of attacks were at night) and that animals with white markings that stand out like beacons in the moonlight are even easier to attack.
    Tswana cattle normally have a brown base color with some animals having white markings. I'm pretty sure that if you add completely white animals to the mix they would be first to go before even the piebalds. But Tswana cattle luckily doesn't tend to be white.

    In contrast, in the absence of night time predators that will hunt throughout the night: There is a feral, piebald herd that's recently descended from dairy cattle in the exclusion zone around Chernobyl. They seem to do pretty well with calves being born and are surviving in an area with a high density of wolves, has Brown Bears and also has packs of feral dogs.
    Researchers have pointed out that the abundance of wolves within the Chernobyl exclusion zone compared to other nature reserves in the region is more than 7 times higher because of the near absence of humans and traffic. They cattle don't seem to be at much of a disadvantage as a result of them being pied compared to the Wisents that also live in the area. So, as much as I like to see my bovines in wild coloration I don't think being piebald is always a disadvantage.

    The Chernobyl cattle also live there with lynx, wisent, przewalski horses, red deer, moose/elk, roe deer, beavers, foxes, badgers, wild boar, golden jackal, raccoon dogs, birds of prey and small mammals and birds etc. This abundance of species I think makes the Chernobyl exclusion zone one of the most complete European ecosystems with numerous large herbivore and predator species being present.
    It's a very interesting area to make observations about European wildlife interactions and what ecological niches the species can occupy. I hope more research will be done in the coming years.

    https://en.newizv.ru/news/world/23-03-2021/feral-cows-in-chernobyl-began-to-live-according-to-the-laws-of-their-ancestors-and-they-feel-great

    https://www.youtube.com/watch?v=16NRqk1ElkA

    https://www.sciencedirect.com/science/article/pii/S0960982215009884

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    1. There were completely white cattle in the study too, the lions prefered the piebald ones.

      When all of the individuals are piebald, as in the Chernobyl population, it doesn't tell us if piebald individuals are in a disadvantage because only that allele(s) is present. If the population was heterogeneous on that aspect, it would be more interesting because we could see if the frequency of piebald individuals decreases over time.

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  6. Tiger Tackles Cow, etc.:
    https://www.youtube.com/watch?v=ZG_qXWK_cXs
    https://www.youtube.com/watch?v=eGXQchJozZE



    http://tigercanyon.com/game/
    https://en.wikipedia.org/wiki/Roan_(horse)

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  7. It would really be interesting to use the chernobyl exclusion zone to breed back aurochs via Taurus/Tauros/Uruz or whatever project. I am pretty sure they will soon have too many bulls, and just sending a few of them over could have a large impact on the long term genetic composition of the population.

    It would be especially intesting due to the wolf predation.

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  8. Very interesting, especially if Lions are ever to be reintroduced to the mediterranean (or bred-back Aurochs to north africa).

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  9. Five lionesses acquire mane and start acting like lions
    Scientists in Botswana detect a physical and behavioral change in several females:
    https://brasil.elpais.com/brasil/2016/09/23/ciencia/1474643418_516188.html

    Lionesses that grow with manes and act like lions in Botswana Five lionesses from Moremi, near the Okavango River in Botswana, grew up with manes and act like lions. Will they be confused? Experts point to high testosterone as the cause.:
    https://observador.pt/2016/09/27/leoas-que-crescem-com-juba-e-agem-como-leoes-no-botswana/

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    Replies
    1. Could you please, please, please stop posting links on my blog all the time? It starts to become annoying.

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