11 Extinct Deer That Aren't Actually Deer

Added: 2026-06-04

[00:00:00]Deer are one of the most common groups of mammals found in our modern forests and plains. There are around two million deer of different species in the UK alone. Sure, the UK isn't that good of an example considering there's barely any truly wildland left, but the fact that they've been able to survive the harsh, unpredictable environment known as Britain is a pretty good indicator to just how successful and adaptable these animals can be. This success is partially due to its body plan. Having long legs and a slim build allows for an effective way to evade predators while not requiring much energy to fuel. This basic shape has been developed by many mammals for the last few tens of millions of years. The family served day, the group that contains all true deer, have taken this body plan and added something even more effective onto it. Antlas used for almost every purpose that can be imagined. Defense, display, communication or intimidation. This diverse group of animals have spread throughout the world, utilizing this unique part of their body. True antlers are unique to deer. For a structure to be considered an antler, it has to be made of bone and felt only. No keratinous horn. It also has to be shed by the males of the species, usually on a yearly basis in the winter. But the general appearance of antlers aren't all that unique. While it's true that today the only animals that have crazy branching structures made of bone on the ends of their heads are deer. Throughout the last few tens of millions of years, multiple different groups of animals have evolved to look eerily similar to modern deer despite having no real relation to them. So today we are going to discuss every time deer evolved, or rather things that look a lot like deer and are sometimes even called deer but aren't actually deer and their evolution.

[00:02:08]Let's begin with Cryptoseras, one of the weirdest creatures on our list today.

[00:02:13]Cryptoseras lived in North America for a long span of Paleo history. Its fossils can be found from the beginning of the Meioene 23 million years ago all the way up to the middle plyiosene around 3 million years ago. Meaning that this one genus existed for nearly 20 million years. It belonged in the family protoeratay, a really strange group of animals that aren't fully understood.

[00:02:38]They're typically placed within Roman archer, the largest suborder of mammals that contain everything from cattle, giraffes, and true deer. Other authors disagree with this identification and place them within Tyler, the suborder that contains camels, alpacas, and llamas. I love a llama. To be honest, most of the members of Protoeratay could be placed on this list. Generous such as Syninderas or Protoseras looked like they belong on another planet altogether. While the generosis and Synthoeris had strange horns above their eyes that really did resemble the antlers of deer, but we've chosen Kryptoseras. I think I called them kryptoseras at the beginning.

[00:03:22]We've chosen them to be the main representative of this group as it probably looked the most like modern deer. It was also the largest member of its family, landing somewhere in size between the modern fow deer or redder.

[00:03:34]So fairly large with a set of spikes just behind its nose and another larger pair above its eyes. This animal really looks like someone tried to draw a fusion between a bronier and a deer, birthing an unholy abomination that I all of a sudden want to stop talking about.

[00:04:07]Next is Hoseros. Hoseros lived in North America during the middle plea scene between 1.8 million years ago to 300,000 years ago. It was a member of the family antillocaprade.

[00:04:20]A group of animals that today just has a single living member, the prongghorn. I slayed that name. While prongghorns might look like a type of antelope or goat, their closest living relatives are actually giraffes. Heeris resembles the modern pong horn but bears a few main differences. It was slightly larger at almost 2 m in length and was probably bulkier in life. But its most striking feature were the two sets of horns above its eyes. The front pair forked out into two separate spikes, very similar to the horns of modern prong horns. But in addition to this, it had a second set of horns just behind these ones that stuck straight up, kind of like a modern gazelle. These unusual features make this animal resemble many different groups of mammals, including modern deer.

[00:05:14]Would you like a banana?

[00:05:25]Merryosiseras is another extinct genus of prongghorn, but this genus is known from just a single species and it isn't very well understood. Its type specimen was found in California in rocks dating back to the early measine epoch around 15 million years ago. This makes this genus the earliest prongghorn to have been discovered so far. Due to the rarity of its fossils, we don't know fully when it evolved or and when and how it became extinct. It was a pretty small animal about the size of a modern fow deer and had a body shape similar to the modern mutjack deer with stockier legs and a larger body. While parts of its skull and horn structure have been found, these remain incomplete enough to allow some artistic liberty with its reconstructions.

[00:06:15]Some depict the animal with antlers very similar to the modern fow deer, broad palmated antlers in the shape of open hands. Others reduce the size of the structure to more of a horn resembling an open Venus fly trap.

[00:06:31]>> OH MY GOD.

[00:06:36]WE are going to discuss one last extinct prongghorn and finish with the most dearlike member of the group and indeed one of the most dearlike animals on this list, Rammo Seros. When researching this video, we completely ignored this genus right up until the end because we thought it was actually just a genus of deer under serveday. But despite appearances, Ramoseris was a genus in the family antillocrade.

[00:07:02]Just like Heaseris, Mariamoseris and prongghorns, it lived in North America during the middleene between 14 and 10 million years ago. Its most striking feature was of course its antlers, which are nearly identical to modern deer antlers with multiple times and even a burr circle connecting it to the skull. If you found this antler on its own, you really would think you'd found a deer antler. Moving down from the antlers, even its skeleton is eerily similar to deer with thin, long legs, a small body, and a relatively long neck capped with a small head. But despite all of this, it wasn't a deer. Not even close. This is best evidenced with its teeth, which are nearly identical to those of the modern prong horn and quite different to those of modern deer. Its most unique feature, which also sets it apart from modern deer, were its asymmetrical antlers. In every specimen of this genus found, one of its antlers, it varies from left to right in individuals, just like the tusks of narwhals, is always at least three times larger than the other. The reason for this is currently unknown.

[00:08:16]Rammeseris is closely related to other gener such as Kerix and Mary Kodus, both of which have horns that strongly resemble the antlers of deers. But I wanted to shed light on Ramoseras as it bears the most resemblance to modern deer and has the weirdest antlers. The next few entries on our list are all members of the family giraffe a day.

[00:08:38]Currently, there are two living members of the family giraffes and okappy. But it turns out that this was once an incredibly diverse group of animals that at one time spread throughout much of the old world, filling a variety of niches and body plans, some of which were very similar to modern deer.

[00:08:57]Giraffits are most closely related to cattle, antelopes, and deer, which is why all of these animals possess some kind of horn structure above their eyes.

[00:09:07]While modern giraffes and okappy have reduced these ornaments to small horns called an oiconee, some of their ancestors really ran wild with these structures. So much so that some of them looked quite deerike at first glance.

[00:09:31]We will begin with Sathetherum. Our largest entry on the list and also one of the most dearlike lookers. Sathereum lived from the late measine around 7 million years ago all the way up to the middle plea scene 1 million years ago.

[00:09:47]They had quite they had quite a run of it. It lived in Africa just like its modern relatives, the giraffe and okappy. While its body resembled an okapy more than a giraffe, it was far larger than any living opp. In fact, while its legs and neck weren't nearly as long as the modern giraffe, it was such a heavily built and massive animal that it still rivaled modern giraffes in term of general mass. The largest member of the genus severthetherum gigantis inventive is estimated to have a maximum size of over 1,300 kg making it one of the largest ruminants to have ever lived on par with the likes of the giant deer, American moose or modern bison. It also had some interesting horn ornaments which may have resembled modern deer antlers. Different depictions of this animal will give it different oscup deer antler on its head. Regardless of what was actually going on, remember that this was a truly massive animal.

[00:10:54]Even the smallest oiconee depictions would still have weighed as much as your average dear antler.

[00:11:09]Next is Bramarium. You'd think with such a strong contender as the first giraffe on the list that the others would be boring, but ancient giraffes just get weirder and weirder the more you look into them. Bramatherum lived during the late measine between 10 and 5 million years ago in southwest Asia and would have looked quite similar to severe in life. But its osc were very different.

[00:11:35]Basically, it would have had a crown. It had four branching spikes that fuse strongly at the base, giving it a very tall, heavily built set of spikes on its head that almost looks like the upside down base of a tree. Now, admittedly, you wouldn't be mistaking this animal for a type of deer, but it was just too cool not to mention.

[00:11:55]>> Whoa.

[00:11:58]Are you a a giraffe? Another extinct species of giraffe, shanstherum, is another example of an animal that wouldn't really be mistaken for a deer in life, but still developed really unique oiconeses that superficially resembled antlers. Shanstherum lived during the late measine of China. The genus developed body plans that would have resembled the modern moose with shorter legs and a much shorter neck than modern giraffes. Certain species also diversified their oiconeses into a number of different shapes. The species s fuguencis split their tall oiconeses into paired spikes, giving them four points that sort of resembled the horns of prong horns or the short antlers of a deer. Others such as s to leggy took this plan and went even further, broadening their hind oicone and adding small spikes to it so they resembled antlers even more. Honestly, ancient giraffes are so cool. I don't know why people don't talk about them more.

[00:13:04]>> Next is giraffe aerics. Most notable for its terrifying skull. This utter beast of a genus of giraffe expanded its oiconeses to the point they covered most of the top of its skull. Girafficar lived during the middleene between 15 and 10 million years ago in Europe and Asia. It was about the size and shape of a modern okapi. Certain species such as G punja biensis adapted their osicones to become much broader, taller and sharper. Their first set of osc migrated closer to the nose while the second remained above the eye making them similar to kiperas the first member on the list.

[00:13:49]And now that we have done away with the giraffe a day family, finally we can move on to more confusing niche extinct animals that are barely understood.

[00:13:59]Luckily, our next entry, Proltherum, has a confusing and uncertain taxonomic status. Yay! Prolibtherum lived in northeast Africa and the Middle East from between 17 and 15 million years ago during the Middle Meene epoch. Well, its taxonomy isn't entirely undisputed. A study from 2010 placed it in the family climacer, an enigmatic group of unullet that is believed to be closely related to the ancestors of giraffes. But a bit more recent study in 2022 found it to be part of a separate family, prolotheray.

[00:14:38]Prolibtherum could grow to be nearly 2 m long and would have resembled a mix between an okapi and a deer. The most interesting thing about this genus is the insane level of sexual dimmorphism between the males and females of the group. Females had long straight horns on their head that sort of looked like a large antelope horn or a deer's antler without times. The males, however, had a huge flat sheet of bone above their head that kind of looked like massive like a massive butterfly on their chromedome.

[00:15:14]They would have expanded to such an extent that the lowermost portion of the structure had to sharply curve to not obstruct the male's vision. Crazily intricate bone structure on top of the head that tied directly with sexual dimmorphism. That sounds very dearike to me. Suspicious wink.

[00:15:41]Okay, so I know there's no one out there who's going to mistake this animal for a deer, but I put it towards the end of the list because I wanted to spice things up a bit and because the idea of an antlid reptile is pretty awesome and I think most of you will agree. Also, it's my list so I can do whatever I want. A steamosucus was an extinct thorrapid, an enormous group of animals that include all living mammals, even me. And so like Dimetradon, it wasn't a true mammal nor reptile, but a funny kind of in between divergent thing. It lived during the middle perian around what is today Eastern Europe. A few species have been described, but the one we're specifically focusing on is e miraabbilis since that's the one with the coolest headgear. This species possessed two sets of expanded regions on its skull. one located where our zygomatics are today, which resemble a similar structure in intellants, and another above each eye, projecting up and branching out to seem like a small kind of antler. Of course, in life, these projections wouldn't have looked like antlers. They likely would have been covered in a keratin sheath, and some artwork even depicts them as brightly colored. And the rest of the animal was even less dear-like. The name Esteemosucus means crowned crocodile.

[00:17:03]So, you can already gather what its body looked like. It wouldn't have been furry, wasn't particularly mobile or agile in the slightest. And all in all, it's best to compare this to a crocodile rather than a deer in every aspect except it's pretty sweet horns.

[00:17:29]And now for the final extinct animal on the list. And don't worry, we've saved the most deerlike one for last.

[00:17:35]Climaceras.

[00:17:37]This genus lived in the meiosene of central Africa. Two species of the genus have been recognized, both with very different horn structures. Both species were proportioned very similar to deer and were about five feet tall at the head, making them intermediate in size compared to fow and red deer. The species C africanis had tall straight horns with spikes protruding all over them. While this didn't make them look too dear-like at first, these structures actually look really similar to the species Megaloseras Cevini, a deer the size of the modern fow deer that was very closely related to the giant deer Megaloseras Giganteas or the Irish elk which I hate.

[00:18:22]>> Hello, dear of definition here. When Amelia says she hates the Irish elk, she is expressing her disdain not for the animal but for its name. The Irish elk did not exclusively live in Ireland, nor was it closely related to elk, a name referring to both the whoity of North America and the moose of the same continent in Europe as well. In fact, the closest living relative of the Irish elk is theow deer. Deer of definition out. See you brochure bh gabrioa.

[00:18:51]>> The second species c gentri had crescentshaped horns with many spikes emanating from them just like the antlers and hines of true deer. The bottom of the crescent even superficially resembled the brow tine of true deer, the lowermost spike that most species of deer have and use mainly for defense. Now, I know we said that this was the last deer to mention, but we wanted to point out a couple of non- deer that are still alive that aren't actually deer, and there's two of them.

[00:19:22]So, here we go.

[00:19:28]The first of our two extinct non- deer is the mouse deer. As it's helpfully named found in the forests of southern Asia, the mouse deer isn't actually a true deer. The mouse deer of the world have been split into three genera and 10 species. And these together make up the only living members of the infra order, Traulina.

[00:19:53]They are often classified as the smallest deer, despite them not actually being true deer. The title of smallest true deer goes to the absolutely adorable poodoo. I love them. The group has remained almost completely unchanged since the eosene and still retain the saber teeth that early deer and their relatives had. And finally, we have the musk deer. The other living deerlike animal that isn't a deer. Eight species make up the genus Moshkus, which is the only living member of their own family, Moshkaday. They're actually more closely related to cattle and antelopes than they are to true deer. They might not have antlers, but they have every other characteristic of deer, including even longer canine teeth than the mouse deer.

[00:20:44]They evolved in the illegene of Europe, but are now only found in southern Asia, most commonly around the Himalayas. This almost brings us to the end of our video today, but there were a few honorable mentions we thought worth a spotlight.

[00:22:00]Right, that brings us to the end of the video today. Thank you so much for watching. Now, did you guys know that 85% of you right now are not subscribed to me? I think there's something we can do about that, right?

[00:22:19]I'm waiting.

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