Now that is an amusing objection.
There are some people who think that if you run thousands of generations of fruit flies in a laboratory, where the environment never changes (compared to the real world, in the field), with no inter-species rivals, no predators, and no food shortage… they are still supposed to change into something else.
That’s a hoot. Ignorance isn’t.
And eliminating ignorance is my mission:
Sam Gon, III writes:
“The common ancestor of birds and mammals … occurred at the split of the Sauropsida (Reptiles) and Synapsida (ancestors of mammal-like reptiles). The distinctive temporal fenestra in the ancestral synapsid first appears about 312 million years ago, during the Late Carboniferous period.”
“Although the mammal-like reptiles (Therapsida) appeared as early as 285 million years ago, nearly all were driven extinct in the end-Permian extinction crisis 245 million years ago that erased 90% of life on Earth.”
"True mammals first appeared following this major extinction event that marks the start of the Mesozoic, as archosaurs of that time evolved into
- dinosaurs and
- birds. "
Readers will note that within the Snapsida (a class of animals that includes mammals and extinct precursor populations that are more closely related to mammals than reptiles) - - there are 3 major dead ends:
- the Dimetrodons
- the Dicynodontia, and
- the Thrinaxodon.
A similar pattern can be seen on the Sauropsida (Reptile) side of the tree, with lines that were separate from Archosaurs and Turtles, but were wiped out before the present time.