The scientific community has learned about a few very old examples motherhood. Among them is a 306-million-year-old fossil immortalizing two lizard-like creatures huddled together in a tree stump—presumably, researchers argue, a mom protecting its kid.

If that’s indeed the case, this rare fossil could represent an extremely ancient instance of parental care in amniotes, the group that includes today’s mammals, birds and reptiles. The behavior, which requires an adult animal to invest time, energy and resources into its offspring after birth, might sound intuitive for modern creatures, but may not have come as easily to our egg-laying predecessors.

“Parental care is a strategy with a long antiquity,” paleontologist Arjan Mann told Smithsonian magazine last year. “Clearly, it’s worked out multiple times in evolutionary history. And we should have an appreciation for it.”

The amniote clade (within superclass Tetrapoda) represents animals that produce an egg with protective membranes that allow the egg to be laid on land or gestated within the mother. It is a crown group comprising all living mammals and saurians (reptiles and birds), together with all extinct species descended from the last common ancestor of all living mammals and saurians.

https://www.smithsonianmag.com/smart-news/seven-things-weve-learned-about-animal-and-human-moms-year-180974826/

thank you for highlighting the fallaciousness of the Reptile category.

dv said:

thank you for highlighting the fallaciousness of the Reptile category.

If only you knew more, you might contribute more.

https://www.smithsonianmag.com/science-nature/306-million-old-fossil-parental-care-180973833/

PermeateFree said:

dv said:

thank you for highlighting the fallaciousness of the Reptile category.

If only you knew more, you might contribute more.

Actually, me too. What they call “sauria” I had down as “sauropsida”. There are a huge number of clades in between, but none that affect currently living animals.

Sauria turns out to be the last common ancestor of the lizards and crocodiles.

Hey, hold on. Which chart is correct? This one puts the chelonia/testudines as sauria, but according to wikipedia (shown below) the chelonia/testudines are much more distant, and the last common ancestor of chelonia/testudines and crocodiles is sauropsida.

So where do the tortoises/turtles actually fit? Aha, the chart below is actually wrong, very wrong. And the chelonia/testudines and crocodiles are actually closely related. And it is the sauria that contains the last common ancestor of all extant reptiles (as well as dinos, pteros, marine reptiles and birds).

PermeateFree said:

dv said:

thank you for highlighting the fallaciousness of the Reptile category.

If only you knew more, you might contribute more.

I guess “You’re welcome” would be a more convenient alternative response but you do you.

dv said:

PermeateFree said:

dv said:

thank you for highlighting the fallaciousness of the Reptile category.

If only you knew more, you might contribute more.

I guess “You’re welcome” would be a more convenient alternative response but you do you.

You are such an arrogant prick, you even outdo Trump. Understand instead of typing tripe.

honestly, I try to be civil…

maybe civil like civil disobedience

dv said:

honestly, I try to be civil…

Devious is a very good description of you. Well done to whoever pinned you with it as it was spot on.

civil, devil, Advil ¿

SCIENCE said:

maybe civil like civil disobedience

more like civil twilight

dv said:

SCIENCE said:

maybe civil like civil disobedience

more like civil twilight

naughtical disobedience would be more amusing

We should write a Twilight trilogy called Civil, Nautical and Astronomical

dv said:

We should write a Twilight trilogy called Civil, Nautical and Astronomical

at the end it’ll be a full set

dv said:

We should write a Twilight trilogy called Civil, Nautical and Astronomical

PMSL.
——————
Anyway, although I’m sure we’ve discussed this once before, just to clarify my thoughts, the anapsids with 0 holes, synapsids with 1 hole and diapsids with 2 holes didn’t evolve in the obvious sequence 0 → 1 → 2, or in the sequence 1 → 0 → 2. What were the primitive amniotes? Call them A.

Then the evolutionary series was A → 1, A → 2 → 0. Jumping from diapsid to anapsid without passing through an intermediate synapsid.