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Has the evolution of mammals and of the human race been a steady progression of increasing body size, or were there periods when our ancestral lineage underwent significant decreases in body size? Can the possibility be ruled out that we have direct ancestors which were larger than human beings? I can't think of a particular epoch in which this could have occurred. There could perhaps have been a large synapsid in our lineage, or perhaps there was a very large fish.
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>>2454819
It would've been before the Cenozoic, if it happened at all. First maybe see which animals went from small to big to small. Off the top of my head I can only think of some island dwarfism examples in mammals, and I think they are kind of a dead end. Maybe just growing big eventually always ends in major extinction events?
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>>2454834
>Maybe just growing big eventually always ends in major extinction events
That's exactly what I was thinking. The same could also be said about obligate carnivores and highly specialized herbivores. Our ancestral line is probably all omnivores.
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>>2454819
oh hey, you discovered Cope's Rule over 100 years after he did.
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>>2454819
I think there was a study that said bony fish were descended from armored fish so it could be possible
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>>2454819
Animals in general evolving to be smaller doesnt happen too often. It can happen, sure, but typically when the environment starts selecting against animals being larger, it's already too late for them, especially if they're REALLY big. Large animals tend to reproduce a lot more slowly, so its harder to keep up with that. Things like Food availability being reduced would be devastating to a very large species, since something like that can happen very abruptly
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