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Crying Wolf (Life Sciences)
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Ishmael


In: Toronto
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It seems apparent to me that all animals have a natural aversion to human beings. I've got this sneaking suspicion that, to the rest of the animal kingdom, human beings just smell really really awful.
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Hatty
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In: Berkshire
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Scientists have shown the Mongolian horse is not 'the last wild horse' after all but descends from much earlier domesticated horses

Research published in Science today overturns a long-held assumption that Przewalski's horses, native to the Eurasian steppes, are the last wild horse species on Earth. Instead, phylogenetic analysis shows Przewalski's horses are feral, descended from the earliest-known instance of horse domestication by the Botai people of northern Kazakhstan some 5,500 years ago.

The findings signify there are no longer true "wild" horses left, only feral horses that descend from horses once domesticated by humans, including Przewalski's horses and mustangs that descend from horses brought to North America by the Spanish.

Odd how a scientific certainty has morphed into 'an assumption'. Now the Botai are thought to be the first people to have domesticated horses. The first that the zooarchaeologists know of, that is

"Once they domesticated horses they became sedentary, with large villages of up to 150 or more houses," said Olsen, who specializes in zooarchaeology, or the study of animal remains from ancient human occupation sites. "They lived primarily on horse meat, and they had no agriculture. We had several lines of evidence that supported domestication. The fact the Botai were sedentary must have meant they had domesticated animals, or plants, which they didn't have. More than 95 percent of the bones from the Botai sites were from horses -- they were in a sense mono-cropping one species with an incredible focus.

The Botai themselves also appear to have become extinct, or migrated eastwards into Mongolia.

"The Botai people seem to have vanished from their homeland in northern Kazakhstan," said Olsen. "Perhaps they migrated eastward to Mongolia since the later Bronze Age people there shared the practice of ritually burying the horse's head and neck pointing toward the rising sun in the autumn, the time of year they were slaughtered. That's a very specific shared trait."


https://www.sciencedaily.com/releases/2018/02/180222145132.htm
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Hatty
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In: Berkshire
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Another Megalithic favourite, the raven, is puzzling biologists (again) due to a process they term speciation reversal (in quotes).

Speciation, where one species diverges into two, is a well-known concept in the theory of evolution. But a new study based on almost 20 years of research has revealed that “speciation reversal”, the merging of two previously distinct lineages, may also play an important role.

Scientists have discovered that two lineages of common raven that spent between one and two million years evolving separately appear to be in the process of such a consolidation. The findings raise intriguing questions about how science should define species – and whether the boundaries are as clearcut as once thought.

https://www.theguardian.com/science/2018/mar/02/two-become-one-two-raven-lineages-merge-in-speciation-reversal

It sounds from the article as if one raven species, the Californian, has died out but sort of lives on thanks to interbreeding with Holarctic ravens, considered a separate species... until now, that is.

Omland first began studying the raven 20 years ago, after he began to suspect that two separate species could have been lumped together. He reported the existence of two lineages: one concentrated in the southwestern United States, dubbed “California,” and another found everywhere else (including Maine, Alaska, Norway and Russia) called “Holarctic”.

The latest paper, published in Nature Communications, provides new intriguing details of the evolutionary history of the two groups. A genetic analysis of 400 birds spanning the geographical range of the two populations suggests that the California and Holarctic lineages diverged between one and two million years ago, but more recently have merged together again and have been hybridising for at least tens of thousands of years. The two populations now comprise pure Holarctic ravens and a group that are hybrids of the two original lineages (the pure California type no longer exists).


The Holarctic is the 'common' raven, the California variety are restricted to California and there's a third cline, the Chihuahuan raven, presumably smaller, which doesn't interbreed with the other two and has an even smaller range.

The paper also notes that a third group of ravens – known as Chihuahuan ravens – which branched off from the California lineage, have remained separate and do not interbreed with the other two groups, despite their geographical ranges overlapping. Scientists are not sure why this is the case.


Could the geographically limited ravens, as per the region-specific Przewalski's horse, be former semi-domesticates rather than separate species as scientists claim?

Despite being genetically distinct, though, the birds look the same, sound the same and behave the same – although it is possible that they were different before they started to merge into one group.
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Mick Harper
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In: London
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Aurelius, you were recently tasked with reading Wohlleben's The Hidden Life of Trees. Would you add Wohlleben's The Inner Life of Animals and report back to the committee in case we need to task Hatty with reading them. Not now, obviously, you're on leave, but when you get back to work.
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Hatty
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In: Berkshire
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A Telegraph journalist, Joe Shute, has published a book called A Shadow Above: The Fall and Rise of the Raven. He says the bird is making a welcome comeback and traced its presence here back to the Iron Age. Evidence of raven remains in burial sites was for ritualistic reasons, he says, and they were not a food source since the birds taste horrible. Joe Shute wasn't sent a copy of TME.
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Ishmael


In: Toronto
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Perhaps their horrible taste was engineered---in order to maximize their lifespan and reliability.
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Hatty
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In: Berkshire
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It may be that crows and ravens are as tasty as other birds but perhaps from superstition or cultural bias no-one wanted to try them. They are associated with eating carrion which is useful but presumably makes them unappetising.
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Mick Harper
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In: London
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It's all immaterial. Hebrideans eat seabirds which are disgusting. We never eat budgerigars even though they are delicious on toast. If ravens are Megalithically useful they will simply not be viewed as edible.
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Mick Harper
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In: London
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An interesting article about the Sernegeti has been sent to me https://cosmosmagazine.com/biology/the-serengeti-isn-t-wilderness-it-s-the-product-of-livestock-farming which is interesting from two aspects.

Firstly, the Serengeti is usually held up (for our admiration) as the last wilderness left on earth (and therefore to be left alone). But if the Out-of-Africa people are right (and anything's possible) then this might be the first wilderness that wasn't left alone. Though that would be a good reason to leave it alone now.

But, as usual, the article doesn't go far enough when it comes to the 'hand of man'. As we have mused from time to time, the cat family has so many peculiarities that it must be suspected it is not entirely natural. Starting with the disappearance of smilodon exactly on cue when humans were starting to put it about, the rest of the cats seem pretty useful for various human functions. Though of course this might arise unwittingly as, say, humans start messing with their natural habitats, eg the Serengeti. Or it could all be natural (anything's possible).

All this applies even more to big cats' natural prey, the deer family. They really are an odd lot. Including their name which I might have got wrong.
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