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Archive for the ‘evolution’ Category

Reeves’s muntjac is native to China and Taiwan. It is not native any place in Europe, but one of the places where it has been introduced is England. The epicenter of their population in that country is Bedfordshire, where this hunt takes place.  The Dukes of Bedford were into promoting deer on their estate, Woburn Abbey, and they were instrumental in saving the Pere David’s deer from extinction. One suggestion is that the muntjac in England derived from Reeves’s muntjac that escaped Woburn Abbey, but they also could have derived from escapees from the Whipsnade Zoo.

Whatever their origin, Reeves’s muntjac have established themselves a long way from their native territory, and they do quite a bit of damage to trees.

And what usually happens is that people are encouraged to hunt the invasives, but as you can see from the selective shooting that goes on this video, the species is now being managed as a sort of game species on many estates. This development should be of no surprise, and it should be noted that island of Great Britain has only two native deer species, the red and the roe. The very common fallow deer was introduced by the Romans and then again the Normans from the European continent.

But the fallow deer is essentially managed as a native game species. The exact same thing is done with Sika deer that have been introduced to Maryland. White-tailed deer are treated the same way in the Czech Republic, as are all the deer that have been introduced to New Zealand.

Whatever their treatment as a game or invasive species, this video does provide a nice closeup of the male Reeves’s muntjac as a specimen. Of particular note are the tusks, which they use for fighting and display.  It is mentioned in this clip that they are “musk deer, ” but this is in error.

This error comes from the tusks that both muntjac and musk deer possess, but musk deer are placed in their own family (Moschidae).  True deer are Cervidae, and all the muntjac species are true deer that fall into the Cervinae subfamily (which includes red deer, fallow deer, and North American elk).  However, they are primitive Cervinae.

Musk deer differ in some morphological characters from true deer in that they don’t have facial glands, possess only a single pair of teats, and have a gallbladder.  They also never have antlers, and all species possess a scent gland on their tail.

The common ancestor of musk and true deer, though, had prominent tusks. The modern muntjac species is unique in that it still has those fangs of the earliest Cervinae.

The other true deer that is known for its tusks is the Asian water deer, which was definitely introduced to Britain thanks to escapees from Woburn Abbey. But it is not closely related to the muntjac at all.

It is also not a musk deer, even though it has much more prominent tusks than the muntjac and never has antlers. Instead, it fits within Capreolinae, the subfamily of deer that includes roe deer, moose, reindeer/caribou, and all the New World deer but the wapiti. Its prominent tusks and lack of antlers are a also primitive trait in this lineage of deer.

That muntjac and water deer are both fanged shows that more primitive animals will resemble each other more the derived forms of their respective lineages.

These cnine teeth are celebrated in North America elk lore. Their “ivory” is taken as almost as much a trophy as the antlers, and indigenous people in Canada and the US used them as jewelry. They aren’t sharp daggers like those found on muntjac and water deer, though. They are just vestigial teeth that show that the ancestor of the great bugling bull were once little fanged creatures.

These upper canines also appear in white-tailed deer on occasion as an atavism.

Beyond these little fangs, North American deer lack these primitive traits, so I find fangs on these Asian species totally fascinating.

They are windows into the past, when deer were just little beasts of the undergrowth.

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coyote  eastern

I cannot tell you how many times I’ve been seen this article from The Economist, claiming that we’re seeing the evolution of a new species of canid that is a hybrid coyote and wolf.

It’s interesting, but I don’t think that just because we have a coyote that has hybridized with wolves and domestic dogs means that a new species is suddenly evolving. Rather, it’s a good example of how some introgression with a related species can provide some potential benefits to a species as it enters new ecosystems.

But the popular naming of this animal is coywolf. To me that suggests that the animals is a 50/50 mix, but the closest we have to 50/50 animals that are 50/50 coyote and wolf crosses are those in parts of Ontario, especially Algonquin Park. Those wolves are around 60 percent wolf and 40 percent coyote .

Most Eastern coyotes are still overwhelmingly coyote in ancestry.

This has led Roland Kays, one of the world’s leading authorities on coyote and wolf genetics (and one of the discoverers of the olinguito), to write this piece in The ConservationHe writes:

Coyotes in the Northeast are mostly (60%-84%) coyote, with lesser amounts of wolf (8%-25%) and dog (8%-11%). Start moving south or east and this mixture slowly changes. Virginia animals average more dog than wolf (85%:2%:13% coyote:wolf:dog) while coyotes from the Deep South had just a dash of wolf and dog genes mixed in (91%:4%:5% coyote:wolf:dog). Tests show that there are no animals that are just coyote and wolf (that is, a coywolf), and some eastern coyotes that have almost no wolf at all.

My little quibble, which is more a gentlemen’s disagreement, is that dogs are part of Canis lupus in the same way that Pekin duck is part of Anas platyrhynchos. They are just domestic variants of a widespread wild species.  Pekin ducks have lost most of their brooding instincts, which means they don’t exist anywhere but captivity. One could say the same thing about bulldogs, which usually cannot free-whelp. They simply wouldn’t exist in the wild, but I think that doesn’t give them a distinct species status.

However, even if we count the dog content in Eastern coyotes as wolves, they are still overwhelmingly coyote in their genetic makeup. If that’s the case, then I think it’s much more fair to call them Eastern coyotes.

If you’re going to call this a coywolf, then you’re going to have call yourself (if you’re not of Sub-Saharan African ancestry) a “humadenisothal.” That’s because modern humans who have origins out of Sub-Saharan Africa have Neanderthal in them, and those who have ancestry in Melanesia and Australia have genes from the now extinct Denisova hominin. All of us are still overwhelmingly Homo sapiens in ancestry, but some humans have the genes of other extinct hominins. It doesn’t mean that we’re all different species. It’s just that different populations have experienced introgression.

Kays is very cognizant of the issues around calling this animal a “coywolf”:

There are many examples of bad animal names that cause a lot of confusion.

The fisher is a large type of weasel that does not eat fish (it prefers porcupines). The mountain beaver of the Pacific Northwest is not a beaver and does not live in the mountains. And then there’s the sperm whale…

We don’t get many opportunities to name new animals in the 21st century. We shouldn’t let the media mess up this one by declaring it a new species called the coywolf. Yes, there are wolf genes in some populations, but there are also eastern coyotes with almost no wolf genes, and others that have as much dog mixed in as they do wolf. “Coywolf” is an inaccurate name that causes confusion.

The coyote has not evolved into a new species over the last century. Hybridization and expansion have created a host of new coyote variations in the east, and evolution is still sorting these out. Gene flow continues in all directions, keeping things mixed up, and leading to continual variation over their range, with no discrete boundaries.

Could evolution eventually lead to a coyote so specialized for eastern forests that they would be considered a unique species? Yes, but for this to happen, they would have to cut off gene flow with nonhybrid animals, leading to distinct types of coyotes that (almost) never interbreed. I think we are a long way from this possibility.

For now, we have the eastern coyote, an exciting new type of coyote in the midst of an amazing evolutionary transition. Call it a distinct “subspecies,” call it an “ecomorph,” or call it by its scientific name Canis latrans var. But don’t call it a new species, and please, don’t call it the coywolf.

Yes!

However, if we want to make things more confusing. We’ve gone down this path of naming all sorts of wild dogs “wolves” for quite some time now. The Falklands wolf or warrah was actually closely related to the maned or “red” wolf. “Red wolf” is the direct translation from the Russian for the animal we call a dhole, and one way to interpret the scientific name of the African wild dog (Lycaon pictus) is “painted wolf.”

Coyotes are very closely related to wolves and dogs. They are something like 99.3 percent genetically similar.

And now that we’ve started to use molecular data to classify the dog family, we’ve generated several new “wolves” that aren’t part of Canis lupus. For example, when I was a child, Canis simensis was the Simien jackal.  Mitochondrial DNA analysis suggested it was closer to wolves than other African canids, so we started calling it the Ethiopian wolf.  Now we know it’s not that closely related to Canis lupus, but we still call it by that name.  My guess is that it is easier to get people interested in conserving a unique form of wolf than it is to get people to want to conserve a uniqiue form of jackal.

We also now know that African golden jackals are more closely related to wolves and coyotes than to Eurasian golden jackals, and we’re now moving to calling African golden jackals “golden wolves” (Canis anthus).

However, if we start calling the African canids “golden wolves,” why aren’t we calling the coyote something like “the lesser North American wolf.” A coyote is much more closely related to Canis lupus than the golden wolves of Africa are.

So you can see that it’s not that trivial what we call this animal.

Of course, calling the Eastern coyote a “coywolf” just adds to the mystique of this animal, and it certainly has plenty of mystique.

Most people in the US don’t live near any wolves. The last wolf in West Virginia was killed around the year 1900. The nearest wolves to me are in Michigan’s lower Peninsula, where they were discovered just a few months ago.

Yet we’ve come to think of wolves as a symbol of the wilderness we’ve lost.

So when the media says that we have “coywolves” running around, then it makes us feel that some of that wild mystery is running about.

Well, it certainly is, but using this term doesn’t help our understanding of what is happening.

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velvet claw

If you probably couldn’t tell from reading this blog, carnivoran evolution and natural history is one of my passions.

Where did all of this get started? I’d say sometime in the mid-90s. I used to watch A&E’s old Wildlife Mysteries series on Thursday nights. These were mostly very high quality wildlife documentaries and a lot of them were BBC productions.

Some of these films were shown in a series called “Carnivores.” It was about the evolution of the order Carnivora, minus the pinnipeds. And I loved it.

The series was based upon the work of David MacDonald, a carnivoran specialist and conservation biologist at Oxford.

In the UK, it was shown as “The Velvet Claw,” which is one reason I’ve had a few problems finding even clips of it online.

And for a long time, all that we could see are short clips, but now, well, it’s been uploaded in full.  Here is the entire series on Youtube.

I don’t know how long it’s going to be up, so you’d better watch it soon.

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sumatran rhino

A few days ago, I had a discussion on Facebook with someone about Sumatran rhinoceroses and why they were still hairy. I had posted one of Frans de Waal’s photos of a Sumatra rhino calf, and as calves go, it was very shaggy.

The discussion got to a really interesting question, which I think points out to a misunderstanding of the mechanisms by which evolution happens. The discussion went something like this:

“Sumatran rhinos are hairy. Therefore, there must be some reason they are hairy. Otherwise, there would be selection against having lots of hair in jungles of Southeast Asia, Borneo, and Sumatra.”

The answer I had was that the Sumatran rhino is the closest living relative to the extinct woolly rhino. Woolly rhinos were quite well-furred out, and it’s possible even now for animals to retain primitive traits. You hear people talking all the time about living fossils, but there is usually no understanding that a 20 million-year-old shark that looks very similar to living species most likely is incapable of reproducing with that living species (if the two were made to live contemporaneously with each other.)

The error is in assuming that a trait an animal possesses is always a benefit to it. This is a corollary of thinking the evolutions happens through natural selection alone, when it is actually only one way that it happens. (And it’s actually not the main way).

The truth is the Sumatran rhino is nothing more– or less– than the last survivor a lineage of rhinos that retained their furry bodies of their tapir-like ancestors. (And Sumatran rhinos aren’t even that hairy!).

And it should be noted that there are plenty of mammals in the Sumatran rhino’s range that have much furrier bodies.

Evolution isn’t planned out. It can only work with what genetic material is available in the population. Assuming that Sumatran rhinos retain their excessive fur only because it has some advantage to them is putting the cart before the horse.

Now, there is a possibility that there is some advantage for these rhinos to retain the very furred up bodies. I’ve not seen any literature that explores this possibility, but the fact that this animal is so closely related to the woolly rhino kind of provides the best explanation. This animal retains a primitive trait solely because that’s what its ancestors were. It just can’t magically evolve a relatively hairless body.

So always be careful in assuming that a trait exists solely because there is some advantage to it. That’s a real problem in our popular understanding of evolution.

Be very careful of putting the cart before the horse. Sometimes a trait is advantageous. It’s often just neutral.

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pygmy three-toed sloth

Defining species and subspecies is a complex task. Lot of ink gets used in peer-reviewed journals debating if a population is a true species, a subspecies, an ecomorph, or a mere local variant. There is no cut-and-dry definition for any of these classifications, which is actually one of the strongest pieces of evidence for evolution. If all things were specially created, it would be very easy to determine species statuses. You wouldn’t have all this debate at all. It would be very easy to settle.

Long-term readers know that I’m skeptical of considering dogs a separate species from the wolf, even if it is not politically correct in some dog training circles to say so. I’m also skeptical of species status of the red wolf and the “Eastern wolf,” which are almost certainly just hybrids with wolves and coyotes. I’m skeptical that the Island fox of the California’s Channel Islands is separate species from the mainland gray fox, but I don’t deny that it is a very unique subspecies.

Part of my reasoning for being skeptical of the Island fox’s species status is that it only recently derived from the mainland species. These two populations have split from a common ancestor only within the last 9,200 years and may have been introduced to the islands by humans only about 7,000 years ago. For those of you keeping score, dogs split from their most recent common ancestor with wolves at least 15,000 years ago, and when you realize that there are some populations of wolves, especially in the New World, that are even more distantly related to dogs than the common subspecies of Eurasian wolves are, you can see where this gets really tricky.

So if I’m not calling a dog a species, then I really shouldn’t be calling an Island fox one.

If you call an Island fox is a species, then it is perhaps the youngest mammal species on earth.

The only other species that comes close to it is the pygmy three-toed sloth. That species derived the Panamanian brown-throated three-toed sloth about 8,900 years ago, when the island of Isla Escudo de Veraguas became separate from the mainland. Unlike their more generalist ancestor on the mainland, the pygmy sloth lives solely on mangrove leaves, and it spends a lot of time swimming from mangrove to mangrove.  It is 40 percent smaller than its mainland ancestor.

And there are only about 70 of them left.

This sloth and the Island fox are good examples of how rapidly simple barriers to gene flow can result in phenotypic divisions between related populations.

It is at this stage I realize that I have contradictions in my own concept of species. I think everyone who has looked at the issue does at some point.

I’m less willing to think of the Island fox as a species than the pygmy three-toed sloth. But the truth is they are both kind of in that nebulous area.

I’m pretty sure that if you caught a gray fox here in West Virginia and turned it out on the island of San Nicolas, it would mate with the island foxes. If it were a dog fox, I’m pretty sure it would dominate the island, not only because a mainland gray fox is quite a bit bigger than an island but also because these foxes are known for their very tight genetic bottleneck. These foxes have been able to keep their MHC haplotypes diverse and heterozygous because they have a way of picking up on these differences when they choose their mates. My guess is a big mainland gray would be in demand with just about any vixen on the island. Monogamy be damned.

But somehow, I think adding a brown-throated three-toed sloth to Isla Escudo de Veraguas would mess up the uniqueness of the pygmy three-toed sloth. Maybe the hybrids would be unable to live so well on mangrove leaves. Maybe.

Or maybe I’m just finding a way to rationalize it.

This isn’t an easy question. It’s not an easy answer.

We talk a lot about conserving endangered species, but the truth is we don’t have a very good concept of what a species is. We have a lot of different concepts for defining species– all of them good. But every single one of them leads to contradictions like these.

These contradictions are wonderful in science.  They give us things to question, debate, and explore.

But when we come up with something called an Endangered Species Act, what exactly do we mean?

The law cannot handle such nebulous and contradictory definitions. Science explores natural phenomena. The law derives requires clear definitions, or lacking such clear definitions, case law that fleshes out the nebulousness. (At least in common law countries…)

I don’t have any good answers to these questions, and the truth is that no one really does.

That’s because at the core of it, evolution isn’t just something that happened. It is something that is happening, and our human brains, which try to make clear distinctions so that we can understand, intuitively cannot handle the gray area.

We know that the Urocyon genus of wild dogs is a very distant offshoot from all other canids.  We know that three-toed sloths are not that closely related to two-toed sloths, which are the last survivors of the lineage that included those giant ground sloths that once roamed much of North America.

When we get to the finer distinctions between really closely related populations, we really don’t have good answers.

But it’s pretty clear that if we call the Island fox and the pygmy three-toed sloth species, they are very new ones.

Evolution can happen rapidly, but it usually doesn’t.

And islands have a way of making it happen fast.

Those concepts are fascinating in themselves– much more so on which Latin or Latinized binomial we use.

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pekin duck

One of the more bizarre fights that happens in the world of dogs is how to classify them. Within these debate is always a background of what it actually means to care for a dog “naturally” and what their “natural” life should be.

It actually shouldn’t be this way. Whether one considers a dog to be its own species or a subspecies of Canis lupus, there is no natural way to care for them or natural life for them. That’s because a dog is a domestic animal, the oldest of domestic animals, and there is very little that is natural about them. Over the thousands of years that have been part of human societies, they have adapted very nicely to our needs. Dogs have even developed cognitive short-cuts that have made them better readers of human body language than virtually any other animal, wild or domestic.

The natural way of keeping a dog is that a dog lives with people. It’s an oddball among domestic animals in that is derived from a very old domestication, and it is also the only large carnivoran that has ever been domesticated. Almost all other domestic animals are herbivores, and the other domestic carnivorans–the Near Eastern wildcat, the European ferret, and the red fox– are all small species. Most large carnivorans consider humans to be prey, so there is something very unusual about domestic dogs.

I get that.

But I am not among those who thinks that there is a species called Canis familiaris. I think dogs are most correctly classified as a subspecies of Canis lupus. 

As soon as I say this, people just lose it. That’s because when you say this, it is almost like justifying abusive dog training methods that are based upon dominance. It also might be justifying raw feeding, which is also contentious issue in the world of dogs.

Those are implications that I soundly reject. There is nothing inherent in a classification of an organism that tells you how to feed it or train it, especially when you’re dealing with the real oddball among domestic animals.

Note that it is never controversial to say that a pekin duck is a mallard. In the photo at the top of the page, you can see the old pekin drake that used to rule the pond. His mate was that Rouen-cross hen, which was sold at a feed store as a mallard. They were both of the same species. Her ancestors were some kind of Western Europe mallard, while his were wild mallards living around Nanjing that were later transplanted to the area around Beijing, where they were selected for larger size and white plumage.

Both of these animals were quite different from the true wild mallard that I see swimming in rivers here in West Virginia. She was twice the size of a wild mallard hen and much darker in color, and he was three times the size of wild drake. Neither of them could fly very well. The Khaki Campbell crosses in the photo were actually much better fliers than either of them.

Performance-strain Rouens are not far removed from the wild mallard. Although they are larger and cannot fly, they still produce the large amounts of oil in their plumage that keep them warm and dry even when they swim the coldest water. Female Rouens also retain the brooding instinct and can hatch out their offspring.

Pekins don’t produce as much oil and aren’t as cold tolerant, and if incubators didn’t exist, there would be far fewer pekin ducks in this world. Most pekin hens have no broody instinct. Further, they also grow so much more rapidly the either Rouens or wild mallards that they are prone to growth disorders.

Even though it is so far removed from the wild mallard, the pekin duck is still a mallard. It is as much a modification on a mallard as a St. Bernard is on a wolf.

The only difference is that no one is going to launch into a culture war tirade over the classification of a pekin duck, but if you say a St. Bernard is a wolf, then you will be asking for it.

It is certainly true that dog domestication happened a lot longer than mallard duck domestication. I cannot find any good literature on dates for mallard domestication, but it’s pretty clear that ducks have been kept in Southeast Asia for thousands of years.  Dog domestication dates and locations are still quite contentious, but the best evidence I’ve seen suggests that they were domesticated from an extinct wolf population between 15,000 and 32,000 years ago.

Some will argue that this extinct wolf population actually is a different species from modern Canis lupus, but I’m quite skeptical. Wolves themselves are among the most varied species in the wild. If we were to go back in time  see that ancestral wolf population that gave rise to domestic dogs, I think it would be hard to say that they weren’t within the diversity of phenotype that we see in current Canis lupus populations.

I think the big difference is that these wolves had far fewer reasons to fear people and were actually quite curious about our kind and were actually fairly easy to habituate to living near us. Over time, these wolves became incorporated into our society.

Much has been made that dogs and wolves have different reproductive strategies, but the truth is wolves actually have two reproductive strategies. One of these is the pair bond, where a male and female become partners and their grown offspring help care for the puppies. This is the most successful strategy for wolf reproduction because all the resources and attention of the pack can be devoted to a single litter. Another strategy goes on in parallel. Young male wolves leave their natal packs, but they often cannot find a mate or suitable territory. So they often try to mate with the grown daughters that are part of an established pack. These daughters cannot mate with their father, who is pair-bonded to their mother, who will attack them if she catches them in the act. So these females do often mate with these roaming male wolves. They often become pregnant and even have puppies, but in the wild, they almost never get a chance to raise those pups.  In the early years of wolf reintroduction to Yellowstone, prey was so abundant that many packs raised multiple litters every year. One would be born to the mated pair, while others would be born to these unpaired daughters and the roaming males. The way dog genes get into wolf populations is almost always when one of these non-paired females in a pack hooks up with a roaming male dog, which is why dog hybridization in European wolves went unnoticed. Most studies on wolf DNA looked at mitochondrial DNA alone, and if a wolf had dog ancestry coming from a male dog, it simply never would have been noticed.

The pair bond strategy exists because it about the only way to raise wolf pups. It is very common in all other dog species. In fact, a study of Chicago coyotes revealed that they are almost 100 percent monogamous, and similar findings have been discovered in golden jackals. However, in a wolf pack, preference toward the bonded pair during the mating season means lots of stress. They mated pair has to spend lots of time making sure no one mates with the wrong wolf, and they also will try to kill any of the roaming males that come near the unpaired females, which is also why the roaming male strategy isn’t as successful with wolves.  Natural selection would favor pair-bonding over roaming male mating strategies.

Domestication changed this equation. When wolves began to hook up with people, people began to provide food.  These wolves may have pair-bonded and mated in that fashion, but the chances of these secondary females to raise litters to maturity were much greater. Over time, pups born to roamers and unpaired females would start to outnumber those that were born to the pair-bonded wolves, and thus, a relaxation of selection pressures for pair bonding would become ubiquitous in these wolves. When pair-bonding became broken, then it became easier to selectively breed them. One could have a stud that mates with many females, and this promiscuous behavior could have been heavily selected for. Dogs are able to reproduce at much faster rates than wolves do, and one of the weird effects of domestication has been that female dogs are no longer monestrus and become sexually mature at younger ages than wolves or virtually any other wild dog.

Dogs and wolves have continued to exchange genes since the initial split. Black wolves in North America derive from domestic dogs that mated with wolves, as do black Italian wolves.  Wolves in Italy also can have dewclaws on their hind legs, which also originated from dog and wolf matings. Historians ranging form Pliny the Elder to the Plott hound historian Bob Plott have documented cases of hunters breeding their dogs with wolves, a practice that still goes in parts of Russia. It was just recently revealed that the livestock guardian dogs of Georgia have a rather significant amount of gene flow with the wolves of the same region.

So yes, I do recognize there are differences between wolves and dogs, but dog is a modification on the original wolf template.

The final important reason why I classify dogs as being part of the wolf species is that evolution has within it a nested law. This is the law of common descent. One can never evolve out of one’s ancestry. Humans are always going to be great apes, and humans are always going to be primates, not matter how different we become from our ancestors. A whale will always be a mammal, even if it somehow evolved gills.

A dog is always going to be a wolf. We change them through selective breeding, as we have with all our other domestic animals, but we are never going to change their fundamental ancestry.

All that I’m doing when I use Canis lupus familiaris is that I’m putting dogs where they fit on the tree of life. I’m showing my respect to their evolutionary heritage. I am paying homage to their phylogeny.

I’m not making excuses for Cesar Millan or anyone else.

Many people who promote science in our understanding of dogs are actually engaging in what I call “phylogeny denial.”  Many people bend over backwards to show how dogs aren’t like wolves, which I supposed is harmless, but I think it gives people a false impression of what a dog actually is in terms of its evolutionary history. It’s not a domesticated golden jackal or coyote or African wild dog. It is a domesticated ancient wolf, but that wolf was just an older form of the modern Canis lupus.

When you classify an animal according to its phylogeny, you aren’t doing anything else but classifying it. If a whale is a mammal, it does not automatically follow that it is a land mammal, does it? And classifying a dog a subspecies of wolf doesn’t mean that it evolved to hunt moose in Alaska.

I really wish people were taught to think about natural history in this fashion more often. It clarifies a lot of misconceptions people have about evolution. If I had a nickel for every time I get asked about humans evolving from modern chimpanzees, then I’d be a pretty wealthy individual. The last common ancestor between humans and chimps was not a chimpanzee. It may have looked more like a chimpanzee, because chimpanzees retain a lot more of the original African ape’s features than humans do, but it was not a chimpanzee like we have today.

By contrast, the wolves that gave rise to domestic dogs were probably indistinguishable from Eurasian wolves living today. Further, dogs and wolves continue to affect each other’s evolution through a rather significant gene flow. Humans affect chimpanzee evolution only through hunting them for bushmeat, destroying their forest habitats, and spreading disease. There is no gene flow between the two species, and because we have a different chromosome number, any “humanzees” would likely be sterile.

Finally, Canis familiaris creates a stumbling block in understanding the natural history of dogs, which is why you still run into people who think dogs derive from any number of different species of wild dog. Canis lupus familiaris neatens up that confusion very nicely.

Classifying a dog as a wolf shouldn’t be any more controversial than classifying a pekin as a mallard, but dog people just have a much harder time thinking in this way. I have never seen an internet flame war erupt between pekin duck owners over the classification of their ducks. In fact, I don’t think many pekin duck owners actually know that their ducks are mallards and do not actually occur anywhere in the wild.

But with dogs, charlatans have used the dog as wolf idea to justify all sorts of bad human behavior towards dog, but scientific facts remain scientific facts, whether charlatans misuse them or not. In terms of their ancestry, as has been revealed through copious analyses of their DNA, dogs are in the Canis lupus lineage.

They simply aren’t anywhere else in the tree of life. This is where they belong. Accept it, and move on.

 

 

 

 

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Dinosaur denial

I can’t believe there is such a thing!

Source.

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