Przewalski's horse, a close relative of the domestic horses, is still around

Because horses originally evolved in North America, there has been the argument that the arrival of feral horses after 1492 was a reintroduction of a native species rather than an invasive feral population. This is why the US government is in the unique position of protecting a feral population

[deleted]

I learned this in history class in like middle school

The TIL bit, is that the placenta does not develop directly from the mothers body, but rather the egg, as part of its development, differentiates cells into the placenta AND the fetus directly. This only happens to fertilized eggs, so the mother cannot do this on her own. My naive ass thought the placenta was grown by the woman's body. It is not.

The placenta and fetus have HALF the mothers DNA and half the fathers. The father's half is foreign DNA to the mother. This is relevant, for example when the mother and fetus's blood type are incompatible which can lead to the mothers immune system attacking the fetus

I smell a Baywatch reboot

This is like one of those ancient prophecies where a man is told he’ll die in a specific way and he tries to game it, but fate can’t be denied. (“You will be killed by lightning” — so he never leaves the house, and then lightning strikes a tree which falls on the house and crushes him.)

“You will die by drowning”

Oh yeah? I’ll go to outer space, no water there!

No, no clearly all space walks are actually faked in a secret underwater studio. The coolant explanation is just an excuse.

So the egg that was created by the mother grows into a baby and a placenta that were not created by the mother???

Luckily the early detection meant both were fine. But yes. Could have been catastrophic. Thank goodness scans are routinely used.

Yes. Mum and baby fine. Thanks to early detection and the skills of the surgeons. Baby was prem as there had to be no chance of labour starting

God bless those poor flatearth smoothbrains, this is the kind of stuff they jerk themselves off over without even knowing how a spacesuit works.

Cool. Another mystery solved.

Turns out it’s both, dubbed as a mesoskeleton:

https://avp.fandom.com/wiki/Mesoskeleton

Well, in NASA's defense, they probably didn't have a lifeguard on duty in space.

What? You can literally see its bones under its skin. And it has teeth.

Giant moray reach 3m (9.7 ft) and 70kg (154lbs) so not really small.

First time I saw that scene I got lightheaded

I'm more worried about the person who had to carry it.

On the subject of things that can go terribly wrong with pregnancy, look up molar pregnancies and acardiac twins.

With molar pregnancies, two sperm fertilize one egg, or one sperm fertilizes an egg that doesn't contain the genetic material that it's supposed to, and the incorrect chromosome count means that instead of conceiving something that turns into a normal placenta*, the woman conceives this large fluid sac-filled mass. It can grow through the muscle of the uterus and can potentially turn cancerous and metastasize to the lungs, brain, etc. It's also possible to have a fraternal twin situation where one twin is a normal fetus and the other is a cystic mass that generally ends up killing the fetus. This mass produces much more hCG (the hormone that turns a pregnancy test positive) than normal, can cause preeclampsia, and as time goes by without removal the woman will often start passing grape-like cysts from the vagina.

*In the type with the empty egg (known as a complete mole), no maternal DNA is present so it's basically the father's cells that are getting inside the woman, invading, and potentially even killing her. Really odd to think about. In the type where two sperm fertilize one egg, a fetus can form in addition to the abnormal cystic placenta, but it's typically nonviable.

As for acardiac twins, when a fertilized egg splits to form identical twins, depending on exactly when it splits they could end up sharing one placenta and/or amniotic sac. And when they share a placenta, sometimes the blood vessels don't form properly and the twins end up connected to each other. This can result in twin-to-twin transfusion syndrome, where one twin gets a disproportionate amount of the blood and ends up large and beet red while the other ends up tiny and anemic (and one or both may end up dying). In a more extreme case, they can end up with twin reversed arterial perfusion, where one twin (A) ends up supplying all of the blood to the other twin (B). Unfortunately for twin B, they're getting the deoxygenated blood that has already been used by A, so they don't get enough oxygen to develop correctly. They don't end up being able to develop a heart (hence acardiac twin), but some of them don't even develop a head, and just end up being a big mass of flesh with legs and a spine that just stops at the neck. Some of them end up being nothing more than a head with an umbilical cord coming out of the stump of the neck. Treatment involves going in and shutting off the blood supply (after which the now-dead acardiac twin stays in the uterus until birth), but if left untreated, twin B generally gets pretty large and ends up killing twin A because having to supply blood to two bodies causes the heart to fail.

Horrifying.

I know what it is. I just wanted to hear the specifics of this case

And the baby is ok?

"Space" technically includes everything in existence, since the universe is made of space-time, but no it is not completely filled with water. The water came from inside the suit's cooling system which is necessary since without air in space heat can only be radiated away via infrared radiation which doesn't work well and would overheat the person quickly. Bubbles escaping from space suits could be various liquids leaking and immediately boiling as they enter the zero pressure vacuum of space, but I've never seen these videos so this is just an educated guess.

Also, gravity and the magnetic field from our planet prevent the atmosphere from being stripped away by air pressure and solar winds. The further you get from the center of mass of the planet, the thinner the atmosphere until you eventually get to a low enough air pressure that it becomes a vacuum.

The placenta attached itself to the organs and the bowel rather than just the uterus and was getting its blood supply from them. As far as I understand it, if any of those attachments broke, i.e. with labour/delivery mass haemorrhaging would occur. Surgeons had to carefully separate (and cauterise or tie off in some way) each connection. Fortunately it was picked up by scans and could be carefully monitored. Described as the octopus tentacles enveloping the organs.

Everything with xenomorphs points to an exoskeleton. The rapid growth, shed skins and egg-laying especially.