Afrotheria: A Brief History
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- เผยแพร่เมื่อ 7 ก.พ. 2025
- Afrotheria (literally, "African Beasts") includes seven groups of mammals with little superficial resemblance to one another: elephants, sea cows (dugongs and manatees), hyraxes, aardvarks, sengis, golden moles, and tenrecs. Despite their apparent dissimilarities, they are now widely recognised as having descended from a single common ancestor that existed somewhere in what is now Africa and had already diverged from the common ancestor of most other placental mammals.
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It breaks my heart. Sirenians are the sweetest, kindest, and most affectionate peaceful beings on our planet.
You really do want to cuddle them and shield them from all the horrible things on earth.
RIP Hydrodamalis gigas, Stellar’s Sea Cow, you will be missed (you were delicious, though.)
Capitalism destroys everything good 😔
Criminally underrated channel. Also love the mammal talks. We never get these types of focus of the mammalian taxa. Hope the rest of the other four are coming.
I feel so sorry for Steller cows! Would be fantastic to have them around.
“Oh look! Two videos uploaded at the same tim- wait a second why are they the same thin-.....oh one was taken down by copy right...”
Either way, this video is really well done! I applaud you!
Thank you! Damn BBC and their strict copyright claims!
Fantastic video Dr Polaris . Congratulations on 500 subs well deserved. Keep up the good work .
Thanks!
Crazy to think this was a year ago and he had only 500
Why is hearing zoological and even botanical lectures delivered by a dry British accent so comforting?
A lot of them seem to have some pretty funky teeth and noses, is that ancestral or convergent?
A mobile upper lip does seem to be ancestral for Afrotheres.
Congrats on the 500 subs!
Your channel is one if the best in paleo/biology internet community, and I'm sure it will keep growing.
Cheers! Thanks for your support.
I love how elephants and elephant shrews come to be as closely related as they are.
This channel has been a welcome discovery. I have had the best Zoology classes of my life here. Congratulations and very grateful, Dr. Polaris!
Wow. So much of this I have never heard of, and I watch a lot of Science videos. Yours are so thorough, comprehensive, and yet not at all off-putting for their depth.
I love this channel
Yes, you've reached 500 subscribers. Times 64. Besides: very professional video placing the animals in a geographical context.
Fun Fact;
Otter shrews, unlike all other aquatic mammals, move their tails side to side, like a fish or reptile, rather than up an down like mammals.
I had to look them up. They have an almost crocodilian tail, which looks somewhat out of place on a mammal.
@@corneliusmcmuffin3256 I mean, at the end of the day, mammals are distantly related to modern reptiles. Hell, mice and rats have scale like skin on their skin
This channel is criminally under sub'd.
Very good!, thank you.
It's interesting that it seems all the fully aquatic mammalian lineages appeared around the margins of the Tethys.
...ok, ok, Pinnipeds probably came from the North Pacific but none are fully aquatic - never let a fact get in the way of a good story!
I guess the reason might be down to the requirements for becoming fully aquatic:
Having ventured (back) in to the water because the environment is so "welcoming" said environment had better be pretty darn benign until you properly get the hang of it or you'll always want the option to climb back out of it again...
...Does that mean no more new fully marine returnees? I can't think of any suitable or current near future body of water to "harbor" such a development.
...I must go see it it's known where Ichthyosaurs/ Plesiosaurs / Mosasaurs / Marine Crocodiles come from - maybe a "Tethys-like" environment is a requirement for marine adaptation?
Rambling now...
PS
Well that's interesting! After an admittedly quick search it seems every fully marine vertebrate returnee evolved in the Paleo-Tethys / Tethys:
Ichthysaurs - Paleo-Tethys
Plesiosaurs - Paleo-Tethys
Thalattosuchia - Tethys
Mosasaurs - Tethys
Cetaceans - Tethys
Manatees - Tethys
Did you ever get your answer? Now I need to know more about the Tethys.
Plus spinosaurus is also Tethy
Now I wonder what the major predators in Africa were before mammals from Eurasia crossed into Africa.
good question. all the current ones are recent additions.
the ones in south america are well known.
Hyenodonts
Relationships between elephants, manatees and hyraxees was already well known in late 1980s. I know this, because I made a presentation to school of hyraxes and a classmate had one of elephants in the same day, and we were both happily suprised. And I remind manatees, because they were so different, in particular.
I heard that Hyaenodontids might be members of Afrotheria as well.
Yes I've heard about that proposal as well. I would love this to be the case, if only we had more conclusive evidence!
The one thing I can point to that might suggest a relationship with afrotheres is that they evolved in Africa, but that doesn't demonstrate that they're afrotheres.
Is there more evidence?
As it is, the common view is that they're part of the same group as carnivorans and pangolins--the Ferae
Predatory Afrotheria would be really cool.
Hyaenodontids are Stem-Carnivorians
You are opening my eyes to many animals I never knew about
In the end Phenetics was unsuccessful and eventually abandoned in favour of cladistics for a number of reasons, including numerous difficulties encountered owing to convergence (homoplasy, as individual characters assumed to be homologous were not carefully analysed), mosaic evolution, and a shortage of diagnostic characters (Mayr & Ashlock 1991, pp. 195-205). Even so, certain phenetic methods, such as neighbor-joining, have found their way into cladistics, as a reasonable approximation of phylogeny when more advanced methods (such as Bayesian inference) are too computationally expensive. (Wikipedia). Also, with the rise of molecular systematics, distance methods, which are basically phenetic methods, have become popular, although these are vulnerable to the same problems, especially that of homoplasy. (Mayr & Bock 2002 p.180). MAK130321
Great video! Learned a lot from this!
Such a great channel
Hyraxes look so happy!
Why there was no big carnivores in the Afrotheria mammals
These are not animals, these are escapees from The Muppet Show
Some of my favorite mammals yes and objectively damn adorable
Were there any afrotheres that adopted a carnivorous lifestyle ?
What a fascinating video and charming family of mammals. Do we know if there were predatorial mammals during the African isolation?
What's the music used in this video?
Edit: never mind I found it
So besides the insectivores it doesn't appear they filled in many predatory/carnivore niches? Ok I learned about otter shrews a carnivore.
Heynadonts are thought to be apart of the family and would’ve of filled that niche.
Enjoyed reading along in Wikipedia about Hyraxes. Seriously, could you do/have you done a program on the 4 major lineages of mammals? i.e., how these classifications were developed and what is understood about their evolution.
Well done Thank you
What is that weasel-like animal below the Aardvark at 1:18?
An otter shrew, basically a semiaquatic tenrec in a different family.
I recommend everyone turn on the auto generated subtitles just to see it try to spell the 4 names of the 4 mammal groups at the start of the video. I wanted to see how to spell them to look them up next but Aftotheria is the only one it got right but it got 1 of them soooooooo wrong I died laughing.
Is that intro music from crash bandicoot? Lol
I'd like to see a video about Zoomata and whether or not it's a supported clade by the latest evidence
Great video!!! It is amazing how much entrenched popular culture gets wrong - especially in zoology and paleontology. Thank you.
welldone!
These kind animals are reason humans and others surivaved past past extinctions
I have a question; what niches could shrews occupy given rapid evolution?
Elephants don't have nut sacks..... that wasn't a thing I didn't know I didn't know lol 😂😂😂
Sound
is Afrotheria a part of the ungulate family tree?
If they evolved on a continent with no other mammals and so through convergent evolution evolved to fill niches other mammals filled elsewhere, why did no carnivore groups evolve? Some of the insect eaters could have grown in size and evolved into meat eaters. there must have been some other animals there filling that niche, in the way in South America animals related to marsupials and giant birds filled the carnivore niche. What other animals were living there that filled that niche? maybe some non placental mammals, or maybe reptiles or birds. something might have been preventing the insect eaters from evolving into carnivores.
...and young male humans. Up by the kidney en route down the inguinal canal toward sexual maturity.
YOU THINK MOLE PEOPLE IS JUST A JOKE BUT THERE ARE COMMUNITIES OF HIGHLY INTELLEGENT MOLES THAT KNOW STAY UNDER THE RADAR.
i like polar bears but when im watching these other animals i change it great material but not watchable in a seious way
Otter shrews look a bit punk :)
American manatee didnt fear people because Indigenous probaly saw the manatee as people espewsialy if they have the five finger that easy to indentify there was this belief some had that five finger animals where all related which is kinda cool Incorect but a neat organization attempt blending science ??? Naturalism and spirituality