How'd the little herps survive the comet?

I suspect the answer lies in food requirement.

Following the comet impact would come global cooling and a darkening of the atmosphere. Both would kill off plant life wholesale. Long term, this would not matter, since plants leave seeds which can re-germinate once conditions warm up.

However, the lack of plants would be a major problem to large herbivores (obviously) and when they are gone, the large carnivores also die out. Incidentally, this die off would help scavengers such as crocodiles. Especially since crocodiles can go long periods without food, anyway. A nice decaying T. rex at the bottom of the pond might keep a crocodile happy for a very long time. Decay would be slowed by colder temperatures. Whale carcasses at the bottom of the ocean have been observed to be still feeding scavengers a full year after the whale died.

So what is left? Obviously, a hell of a lot of decaying vegetation. This becomes part of the soil, but still supports life. The life it supports is invertebrate. Mites, insects, ants, termites, etc.

The larger life that survives until the regrowth of plant life is mainly insectivorous. This includes small mammals, lizards, birds etc. Plus their predators.
 
Skeptical said:
Especially since crocodiles can go long periods without food, anyway. A nice decaying T. rex at the bottom of the pond might keep a crocodile happy for a very long time. Decay would be slowed by colder temperatures. Whale carcasses at the bottom of the ocean have been observed to be still feeding scavengers a full year after the whale died.
Click to expand...

But surely this event lasted decades or even hundreds of years, not one year. Even a meager volcanic eruption can easily influence the global climate for years. A major impact would be much worse.
 
Hmm. Yeah. Does still kind of leave the small reptiles question open, doesn't it? If we're arguing metabolism...then really tiny dinos should be in the same boat as tiny early mammals, no? Or maybe their body plan was less efficient: no fur on the really small ones, compared to fur on small mammals and feathers on birds.

We haven't even touched on the geographic issue: are these small animals coffin-dodging by moving from region to region? If that's so, it might explain the birds' surviving: they don't call it "as the crow flies" for nothing. But surely there must have been a few examples of every group somewhere on the planet? Although...what about island refugia? Does that seem possible? To use an example displaced into the modern era, you don't find placental mammals native to Australia. Large or small landmass breaking away, say, 220 MYA or thereabouts, uncolonized by dinos of any kind (or of any small kind) but colonized by mammals and birds? Actually, this sounds kind of exciting. I think.
 
Oh, piss on Meropis, says I. Please! We're trying to keep this out Pseudoscience or, even worse, actual science. Let us confine our observations to the realm of speculation.
 
Geoff

I suspect even the small dinosaurs were too big. The smallest I remember reading about was about turkey size. Apart from birds, that would make all dinosaurs too big to survive on a diet of tiny soil dwelling invertebrates.

The crucial period can't have been too long. A few decades at most. Or else, all those seeds would not have germinated. Seeds only survive so long. Once abundant plant life returns, life can rebound. Except those that died out, of course!
 
Skeptical said:
Geoff

I suspect even the small dinosaurs were too big. The smallest I remember reading about was about turkey size. Apart from birds, that would make all dinosaurs too big to survive on a diet of tiny soil dwelling invertebrates.

The crucial period can't have been too long. A few decades at most. Or else, all those seeds would not have germinated. Seeds only survive so long. Once abundant plant life returns, life can rebound. Except those that died out, of course!
Click to expand...

But the size argument fell with crocodiles.

Why would the fault lie with animals anyway? I predict there was a shift in vegetation species arrangement. And that this was the killer blow. An indirect cause.
 
Well...crocs can go a while without eating. Turtles also, but not as long.

Therapods like Compsognathus would require more energy pound-per-pound.

A shift in vegetation would certainly do the trick, I guess. Too much specialization in the smaller dino species? Inability to shift diet? You'd think birds would be the same. Or maybe what we're really seeing is not the all-or-nothing extinction of dinos but not mammals and birds and reptile and amphibian lineages, but extinction of the larger species with survival of therapods in extant and short-lived bird lineages. That's the obvious answer I guess. Just seems unsatisfying. I do like my heresies in biology. It's just odd that most of the modern bird lineages seem to have diversified in the Cretaceous. Almost seems like niche radiation post-K/T, other than the timing of K/T itself ruling that out.
 
In a search of "smallest dinosaur" on the net, I happened to find this:

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Microceratops - ahh make it stop

Creepy. Bipedal ceratopsian.
 
Yep

Birds are the only branch of the dinosaurs to survive.

Microceratops was about the size of a rabbit. But it was a herbivore, so would die off along with the demise of green plants.

My suggestion that only insectivores survived obviously only applies to land dwellers. Obviously, the sea was a very different environment, and the result of the asteroid impact would be quite different in the marine environment.
 
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