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What Made You Happy Today?

Vanessa28

Angel of Darkness
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Yahtzee, Supernatural
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Angel of Darkness
Taco Bell is offering free tacos on Tuesday.

Guess where I'll be on Tuesday? ;)
I wish for you all the most delicious tacos in the world :D


So absolutely satisfied with my first page finish of my pokemon cross stitch project. At first I had my doubts about the final look but it passed all my expectations :D :D
 

thePlinko

What’s the character limit on this? Aksnfiskwjfjsk
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So for context, my grandma lives closer to my college than I do, so usually between classes I go to her house for lunch. This semester the only day where it’s really convenient is Mondays.

My grandma’s favorite movie is Up, which also happens to be one of my favorite movies. She was also the source of about 75% of my LEGO sets as a kid, so when I saw that they were releasing a set based on Up I knew I had to get it for her birthday so we could assemble it together. We decided we’d just knock it out bit by bit when I come over each week for lunch and started on it today. Now my grandma is a very pleasant and cheerful person in general, but I don’t think I’ve ever seen her as genuinely happy as she was when she saw how they designed the little record player inside the house. For the first time in a long time I’m actually looking forward to next Monday.
 

Uwu_Oocoo2

The flow of time do be cruel like that
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My cat had to go to the vet today because she had a claw sticking up a way it's not supposed to. Very happy it wasn't too serious, they were able to give her some antibiotics that should help. They also found an injury on another one of Mia's claws which I'm glad they were able to address. Now we have to look into getting her some stairs, since being old she's having a hard time jumping on things and it's probably climbing onto my dad's chair that injured her in the first place.
 

TheGreatCthulhu

Composer of the Night.
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Jan 22, 2016
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United States of America
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Very much a dude.
A small thing made me happy today, which made my inner zoology and paleontology nerd really happy.

So for many animals, their ancestry can be fuzzy and incomplete, and for many others, their origins and ancestors are quite well known. For birds and dinosaurs, we have loads of fossils, for us humans, loads of fossil ancestors, for whales, loads of fossil ancestors, and so on.

And for lizards and snakes, loads of fossil ancestors, and I've always had a love and fondness for reptiles, with my favorite extant reptiles being turtles.

For a long time, turtles were kind of a mystery, as we only had a few fossils of their ancestors, hypotheses about their evolution were hazy and fuzzy, specifically referring to their skull and shell, as turtles were long thought to be anapsids, which is, amniotes that have no temporal openings in the skull, as sights for muscle attachment in turtles is in the rear of the skull.

Which presented a unique anomaly in reptile evolution and ancestry. Birds, crocodiles, lizards, dinosaurs, pterosaurs, tuataras, and snakes all had clear ancestry, and turtles it seemed, were an evolutionary dead-end.

Turns out, actually, that turtles are diapsids, meaning they are descended from amniotes that have two temporal openings in the skull, they just closed over, as that's what early ancestors of turtles showed. So really, turtles are more closely related to the classic diapsids that I just listed.

Then the debate shifted to whether turtles are more closely related to birds and crocodiles, or to lizards, tuataras, and snakes.

Turns out, turtles shared their most recent common ancestor in the clade where birds and crocodiles belong, called Archosauria, meaning turtles are more closely related to birds, crocodiles, pterosaurs, and dinosaurs. They aren't true archosaurs, they are their own group, known as Testudinata, which are reptiles with a bony carapace and plastron forming a shell.

What's more, more fossil evidence came out showing another unique aspect about turtles: how their shells formed.

Turns out, ancestors of turtles go clear back to the Middle Permian, some 300 million years ago, showing that turtles are not just long lived in general, but are quite an old family of reptiles.

Anyhow, fossils of early turtle ancestors showed that they lacked the carapace, (the back part of the shell), and a plastron (the front part of the shell), but they had shortened torsos, expanded ribs, and lengthened dorsal vertebrae.

In the Late Triassic, that trait continued. Initially, scientists were unsure which part of the shell developed first. Was it the plastron that came first and then the carapace? Was it the carapace first and then the plastron? Or was it both?

Turns out, turtle ancestors in the Late Triassic showed that the plastron formed from expanded gastralia, and the carapace was slowly forming from rib osteoderms.

The first true turtle is Proganochelys, a turtle from the Late Triassic that had a fully formed plastron and carapace, and one of the stem groups in the clade, Testudinata, a group of reptiles with a bony, protective shell.

In this research, I also found out what species of turtle the Teenage Mutant Ninja Turtles are according to the original comics.

They're Red-eared sliders, a species of pond slider turtles that are semi-aquatic.

1024px-Turle124.jpg
 

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