[Darth Vader] Join us, Buck… join us…[/Darth Vader]
Not really. Cats and lions are in the same family, while fish and whales aren’t even in the same class. Assuming you meant whale shark, you’d be in the same class, but lions and cats are still much more closely related than the smallest fish is to the largest fish.
Not to mention the fact that there are no “microscopic fish”.
I agree with others that the OP needs to clarify his/her question before it can be answered. Species general go extinct in “geological time frame(s)”, or they evolve into other species. Some limit has to be placed on what constitute a group. In the example of Lucy (Australopithicus afarensis) and Masai (Homo sapiens), the two are not even in the same genus.
That’s exactly what made me post that-- I remembered that article. It’s a small fish, but it can hardly be called microscopic.
So…
Mammals are a class.
Fish are not one class, but several.
Cats are a family.
Dogs are a family.
Sharks are a superorder, a collection of several orders.
Eukaryotes are even above the top level of kingdom. Whereas the question was about a specific kingdom, Animalia.
So the first thing to settle is: Which taxonomic level do you want the answer on?
A fairly sensible question to ask, and closely related to the most common definition for “species”, but it’s a bit more complicated than that. A chihuahua would at least have great difficulty mating with a Great Dane, and one could conceive of dogs (say) so disparate in size that it truly would be impossible. But even if chihuahuas and Great Danes can’t mate directly, a chihuahua could mate with a beagle, and a beagle could mate with a Labrador, and a Lab could mate with a Dane. So you could without too much difficulty end up with a mutt which had both a chihuahua and a Great Dane in its ancestry. Is that enough to count them as the same species?
They already are the same species, Canis Familiaris.
C. lupus. C. familiaris as a species ceased to be used 15-20 years ago.
They figured out that dogs and wolves are the same species. There are a lot of wolfdogs running around, and maybe even some dogwolves for all I know. Do feral dogs and wolves mate in the wild? I heard that when various breeds of dogs all mutt themselves together in the wild, the resulting type is the well-known “yellow dog.” I wonder what would happen if feral dogs and wolves coexisted in the same territory. Perhaps unlikely since most human-populated areas have already deliberately eliminated wolves as much as possible, and I guess feral dogs would probably not locate very far away from human-populated areas which they arose from.
Yep, as do most members of the genus. Dogs and wolves, wolves and coyotes, wolves and jackals. All regularly crossbreed where their ranges overlap.
Which is one of the reasons why it is still somewhat debatable whether dogs are descended entirely from grey wolves. Genetic evidence suggests that they are, but the fact that they never revert to wolf type but instead revert to yellow dogs is considered evidence against the idea.
You only need to look at what happened in the southern US. Feral dogs have a history of thousands of years overlapping with wolves. In Europe feral dogs have been less common but there have ben plenty of semi-feral or wandering dogs. Mating has been routine, but rare enough that the wolf type has apparently not been depleted.
Not really. The Indians, lacking domestic livestock, had little reason to eliminate wolves so their dogs and the wild wolves lived side by side for millenia. In less settled parts of Europe dogs and wolves also lived in close contact ensuring continuous gene flow.
There’s no reason to assume that. We know for example that dogs inhabited parts of Australia, New Zealand and New Guinea that humans rarely if ever visited. Feral dogs will spread into any niche that they can, they don’t need people, which is why they are termed ferals rather than simply strays.