Marine mammals are famously large, but why is that? And is there a polar bear-sized sea otter in our future?
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2:16 Sea otters may be the "odd-balls" because of that fur. The vast majority of marine mammals have little to no fur. They rely on their blubber and size to keep them warm in the chilly water. Sea otters went a different route -- they have literally the densest fur in the animal kingdom, at 150,000 strands per centimeter square, or 1 million strands per square inch. In comparison, chinchillas, with the densest fur of any terrestrial mammal (so dense that fleas and ticks can't penetrate it!) have "only" a third of that -- 50,000 per cm2. Sea otter fur is so thick that, even after spending hours and hours eating and playing and grooming and sleeping in the water, their skin stays completely dry. So they don't need the massive amounts of blubber and fat to keep them warm. Ergo, a marine mammal that's "trim", as the video put it.
With otters, it might be that their fur is better at heat-retention; it's renowned as the thickest among mammals - so they might've stumbled on an alternative to the 500kg "optimal size". They also do spend some time on land - not a whole lot, but it gives them a bit of flexibility in avoiding orcas and the like.
She's gotten so much better at presenting. Used to be you could hear the anxiety in her voice and the tone and nuances were offputting to a degree. But now the camerashy-ness is all but gone completely and that little nervous inflection where she would end every sentence with a low guttural drone is nearly unnoticeable now. Very good. Keep on making the effort to improve and before you know it you'll be speaking at a professional level.
No animal has ever been recorded having a baby of a different species it’s always a slight variation of the same animal. Just like Bible teaches us. Evolution is a man made religion. Praise be a Lord Jesus Christ.
Interesting talk, thanks. I would have liked some more stuff about the human aquatic ancestor, but if the 500kg rule is true, I guess our aquatic ape ancestors were as big as some of the fattest people alive today, which is interesting 😀🙊🙉🙈
Oh my God! Olivia is sooooo much better in this video than she used to be, not to mention her improved looks. Her hair is stunning and just look at these earrings ). The intonation could be a bit more diverse but it’s just a matter of practice.
Otters also have other methods for heat conservation that might reduce the need for large body size. They have fur that traps bubbles of air for insulation. They constantly groom this fur to make sure its stays as efficient as possible at keeping them warm, and have special oil glands that help with grooming.
Unlike all those other marine mammal groups otters rely on fur for insulation. I believe fur is a better insulator than blubber and otter fur is ridiculously dense. That might be why they haven't got so big.
Not being 500kg could be an advantage to the sea otter’s successful lifestyle (fur trade hunting aside). Unlike the other seagoing mammals they don’t have blubber, instead they have the outright densest mammalian fur which needs constant cleaning to trap an insulating air layer underwater. Extra energy expenditure & time for fur cleaning may preclude the extra hunting needed (25% of bodyweight per day) for a larger body size.
I think sea otters are small because they followed a different evolutionary path. Whales, seals, and manatees have no fur and instead depend on their blubber to keep warm and have the cold water in contact with their skin. Otters on the other hand have some of the thickest fur of any mammal which traps a lot of air and keeps their skin from getting wet. Unless there is some process that puts pressure on them to lose that fur I don't think they'll grow a whole lot larger
Remember, whenever a god botherer tries to be clever with you and starts babbling about evolutionary "changes in type" or "macro evolution" just point out marine mammals like whales and seals.
Proof positive that both of those [nonsense terms that they try to pass off as science] actually happened because nothing evolved air breathing lungs underwater!! 8D
This science-based video starts by giving the finger to science. Stating an mere idea as though it were a fact is arrogant, dismissive, provocative, divisive, and above all, NOT scientific. This video says - with certainty - that the Blue Whale is the most massive animal ever to exist. But while that appears to be true, it's impossible to be certain. This may seem like no big deal, but this kind of sloppy communication is part of why public confidence in science, and expertise in general, has been eroding in the U.S. for decades. It's not a weakness to qualify your statements. If you take it on yourself to communicate science, THINK IT THROUGH. Blue Whales are thought to be the largest animals ever, but unless and until you can PROVE they are, STOP saying it like it's written in stone. People are smart enough to handle nuance, and they also remember all the occasions arrogant-sounding scientists made absolutist claims that turned out to be wrong. Stop being part of the problem!
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