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The Mammal-like Reptiles, or Therapsids first appeared about 285 million years ago near the begiining of the Permian which is well before the dinosaurs. They evolved quickly and many different groups arose. They were very successful until about the end of the Permian, about 245 million years ago, when something catastrophic affected the earth and nearly all of the species then living died out. New species evolved rapidly to fill this empty habitat, among them the first dinosaurs and a few million years later the first mammals.
The first mammal may never be known, but the Genus Morganucodon and in particular Morganucodon watsoni, a 2-3 cm (1 inch) long weasel-like animal whose fossils were first found in caves in Wales and around Bristol (UK), but later unearthed in China, India , North America, South Africa and Western Europe is a possible contender. It is believed to be between 200 MYA and 210 MYA. However Gondwanadon tapani reported from India on the basis of a single tooth in 1994 may be an earlier contender for the title, with a claimed date of 225 MYA.
Early amniotes split into two groups: the sauropsids and the synapsids. The sauropsids have evolved into modern birds and reptiles, and synapsids have evolved into modern mammals. Synapsids split into various groups, one of which was the therapsids. All living mammals do come from therapsids, but synapsids are considered the common ancestor or mammals.
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What is most likely similar to a common ancestor of all vertebrates?
jawless fish
Which of the following is most likely similar to a common ancestor of all?
jawless fish
What organism is the whale most closely related?
Whales are related to the even-toed hoofed mammals. Whales are most closely related to modern hippos, and should share a common ancestor with them.
What does the last name Barber mean?
Most likely your ancestor was a barber.
What do the similarities between the skeletal structures of these four species most likely indicate about their evolutionary history?
These four species are distantly related and share a common ancestor.
What mammal has rabies?
Most, if not all, mammals can be infected with rabies. Worldwide the most common carrier is dogs. In the US the animal most likely to infect humans is bats. Raccoons and skunks are also common carriers.
What are the top 10 most common mammals What are the top 5 most common mammals What are the top 10 most common animals What are the top 5 most common animals?
rat rabbits humans coyotes squirls
What is the order in which humans evolved?
I think you're looking for a monkey-chimp-human sort of answer. However there is not a order in which humans evolved (and are evolving). Humans are most closely related to chimpanzees, followed by gorillas and then orangutangs.Not Orangutang->Gorilla->Chimp->Human.What I am saying is that the common ancestor of chimps and humans was around more recently than the common ancestor of humans and gorillas, which was more recent than the common ancestor of orangutangs and humans.After the close relatives you get monkeys then lemurs. Followed by rodents and then the rest of the mammals.
What has the most in common birds fish amphibians reptiles and mammals?
reptiles and amphibians have the most in common
What animals are represented most likely in the diets of owls?
There are many species of owl with many varied diets. The most common owls subsist on a diet of mice and other small mammals.
If you compare organisms with similar characteristics what indicates recent their common ancestor probably is?
The more similar the two groups are, the most recent the common ancestor probably is.
What species of mammals is most common in the world?
I would guess rats are the most common mammal in the world.
