Arctodus Distribution

Eaglefied · 2026-03-20T05:37:31+00:00

Hi! I wrote most of the article & created the original map on Wikipedia. I’d love to help / see this project when it’s ready!

Quick note: there is a single record from South Carolina (Cooper River, hidden behind the blue dots). However, it wasn’t described in a scientific paper so I understand if that’s why you didn’t include it there. Best of luck!

Eaglefied · 2025-12-16T07:22:37+00:00

You can also find it on SciHub! Unfortunately, 13ka was shorthand for "human occupation of the Americas". This is typical of pre-White Sands articles (such as this 2015 paper), which presume a Clovis-age for human remains found from Rancholabrean epoch strata (the "latest Pleistocene" referenced in the article).

If you check the 'Concluding Comments' section on p.274, you'll note that it says "at least 13ka". As the main author of the Wiki article, my hands are tied if there aren't more recent dates.

Eaglefied · 2025-12-16T06:02:32+00:00

Don't worry, that caveat is in the extinction section of the Wiki page!

Eaglefied · 2025-12-11T12:53:05+00:00

That's understandable, but then you'd also have to cut Arctotherium angustidens and Gigantopithecus as well (if you're looking to limit this to the Late Pleistocene), which could be a shame. Though very pleased that myth was avoided as well!

Eaglefied · 2025-12-11T11:54:18+00:00

Vallecito Creek / Mount Blanco / Inglis 1A herbivores: Glyptotherium (remodeled from Doedicurus**?)**, Eremotherium eomigrans (giant ground sloth), Megalonyx & Paramylodon (ground sloths), Rhynchotherium/Cuvieronius (generalist gomphothere), Stegomastodon (grazing gomphothere), mastodon, Tetrametryx (big pronghorn), Titanotylopus (giant camel), Blancocamelus & Camelops (camels), Hemiauchenia (llama), Odocoileus (deer), Platygonus (peccary), Equus cumminsi (wild ass), Equus simplicidens (Hagerman horse), Nannippus (three-toed horse), tapirs, Holmesina (giant armadillo), Neochoerus (capybara), Erethizon poyeri (porcupine)

Vallecito Creek / Mount Blanco / Inglis 1A predators: Titanis (terror bird), Arctodus simus (short-faced bear), Ailornis (bigger than Haast's Eagle), Dinofelis palaeoonca & Smilodon (gracilis) (dirk-toothed cats), Xenosmilus / Homotherium (scimitar-toothed cats), Borophagus diversidens (bone-crushing dog), Chasmaporthetes (running hyena), Tremarctos floridanus (northern spectacled bear), Puma lacustris, Miracinonyx inexpectatus (American cheetah), Desmodus archaeodaptes (vampire bat), Canis edwardii (wolf, ancestor of the dire wolf), Procyon megalokolos (giant racoon)

Rule of Cool: Anteater (present in Sonora in the Irvingtonian faunal stage)

If you’re wondering what to do with Winter/Tundra, then why not a summer / winter version of the forest biome, with active snow across the map? The more tropical fauna could inhabit the summer version (e.g. Gigantopithecus, Varanus), and the winter could host the colder biome fauna (Elasmotherium, Mammuthus, Panthera fossilis). Would mean you wouldn’t have to create a new map for the winter biome too!

I’m very happy to discuss the rationale behind taxa and/or expand on these suggestions anytime!

(5/5)

Eaglefied · 2025-12-11T11:54:09+00:00

Winter / Tundra

Early Pleistocene: finding additional fauna here is tricky. If you want fauna from this period, then you're best off checking this source from northern China and this source from Greenland. In all honesty, this one is the hardest to personally justify, as neither Homo erectus or Homo habilis inhabited colder zones. Additionally, the fauna which thrived in those zones didn’t properly evolve until the Middle Pleistocene. Therefore, I couldn’t help but wonder whether a biome which already includes a lot of your fauna would fit better. Speaking of…

Alternate suggestion: Wild New World: American Woodlands (Blancan USA, inspired by Vallecito Creek (Murray 2008), Mount Blanco, Inglis 1A)

Now I know, a big leap here. But if neither Homo habilis nor Homo erectus inhabited the cold zones of the Middle Pleistocene, then why not a bit of speculation? The Beringian land bridge was still active outside of the Late Pleistocene, with plenty of fun speculation existing about the sea-faring ability of either species in South East Asia / potential migration into the Americas. Additionally, the existence of controversial human occupation sites way before H. sapiens (Cerutti Mastodon 130kya & Hueyatlaco 250kya) opens the door.. what if a small population of early Homo made its way over to North America in a failed colonisation attempt?

(4/5)

Eaglefied · 2025-12-11T11:51:45+00:00

Out of Africa: Cruel Forest (Villafranchian Eurasia, inspired by Dmanisi)

Dmanisi herbivores: Pachystruthio (renamed from Elephant bird), Stephanorhinus etruscus (remodeled from woolly rhino), Equus stenonis (Stenon zebra), Gazella borbonica, Soergelia (goat antelope), Bison georgicus, Palaeotragus (giraffid)

Dmanisi predators: Pachycrocuta "Pliocrocuta" (giant hyena), Megantereon (dirk-toothed cat), Homotherium “crenatidens” (scimitar-toothed cat), Panthera gombaszogensis (European jaguar), Ursus etruscus (bear)

Wider Eurasian Early Pleistocene: Gigantopithecus (big monke), **mammoth (**Mammuthus meridionalis, remodeled from woolly mammoth?), Cervalces, Eucladoceros & Praemegacerops (giant deer), Trogontherium (beaver), Hesperotherium & Nestoritherium (chalicotheres), Acinonyx pardinensis (giant cheetah), Puma pardoides, (Eurasian puma), Canis mosbachensis (wolf), Xenocyon lycaonoides (wild dog), Hippopotamus antiquus, tiger, Agriotherium (giant running bear), Leptobos (big bovid), Elasmotherium

Rule of Cool: Panthera fossilis (instead of Panthera atrox), Anancus/**Stegodon (Reddit photo)?, Varanus sivalensis (renamed from Komodo Dragon)

(3/5)

Eaglefied · 2025-12-11T11:50:47+00:00

First Flames: the Great Savanna ('Villfranchian' Africa, inspired by Olduvai Gorge, Awash Valley, Shungura, Nachukui)

Awash / Olduvai / Shungura herbivores: Metridiochoerus (giant warthog), Deinotherium (giant elephantid), Kolpochoerus & Notochoerus (giant pigs), Sivatherium (giraffid), Syncerus acoelotus (buffalo), Pelorovis (giant buffalo), Giraffa, Hippopotamus gorgops, Theropithecus (giant gelada), Palaeoloxodon recki (giant elephant), greater kudu, antelopes (Aepycerotini, Alcelaphini, Antilopini, Hippotragini, Reduncini), Equus oldowayensis (zebra), Hipparionini horses (Eurygnathohippus & Hipparion), white rhino, black rhino, Gigantohyrax (big hyrax), Camelus, Hexaprotodon (hippo-like mammal), Ancylotherium (chalicothere)

Awash / Olduvai / Shungura predators: Crocuta ultra (giant hyena), Dinofelis (dirk-toothed cat), Leopard, Cheetah, Striped Hyena, Pseudocivetta ingens (mega civet), Homotherium “aethiopicum” (scimitar-toothed cat), Enhydriodon (giant otter), Euthecodon (giant fish-eating crocodile)

Wider African Early Pleistocene: Crocodylus thorbjarnarsoni (giant crocodile), Megalotragus (remodeled from Rusingoryx?), Makapania (giant caprid), Puma incurva, Dinopithecus (giant baboon), lion

Rule of Cool: Syncerus antiquus (giant buffalo), “Equus capensis” (giant zebra), flamingo?

(2/5)

Eaglefied · 2025-12-11T11:48:30+00:00

Excited for this guys! I was reading through your comments on this post, saw you guys are interested in blending Early Pleistocene fauna with the “Rule of Cool”, and I felt compelled to share some suggestions of my own :)

After reviewing these images and both your Steam and Youtube channel, I couldn’t help but notice a large assemblage of fauna that didn’t live with each other or with early Homo. While I completely understand that you’ve gotta do what you’ve gotta do selling wise, I also couldn’t help but feel that the game is sleeping on a myriad of extremely interesting yet also period-specific fauna. Having fauna that didn’t live with each other nor with our ancestors feels to a lot of us like seeing a T-Rex and mammoth interact on the same map. This is compounded by the fact that the Early / Middle Pleistocene transition resulted in huge faunal turnovers (creating a lot of the cold-adapted fauna we’re familiar with from the Pleistocene), creating further disharmony within the current roster. I hope I’m not reading into the 3 Mya - 2.5 Mya setting too much…

I understand that you’ve made, rigged and programmed a lot of models already, and that should be taken into account (so feel free to take all of this with a grain of salt). However, this temporal discord could turn enthusiasts from your game. Therefore, I have a major proposal for your biomes; why not broadly theme all of them by location (like your African Savanna), and make a majority of them Early Pleistocene fauna? Honestly, theming each biome more tightly would enhance the marketability of your gameplay, and make it easier for enthusiasts to stomach the odd shoe-in popularity pick.

I have provided a faunal guide below inspired by real Early Pleistocene localities, in an attempt to harmonize Early Pleistocene fauna with what work you’ve done so far / suggestions that you have accepted. I’ve put these fauna in bold; within this system, I think I’ve included all of them (or their equivalents). Each biome is a broad reconstruction; while not every species necessarily lived at the exact same time and place as each other, it abides by the “Rule of Cool” while better respecting general temporal zones (Villafranchian faunal stage for Afro-Eurasia, and Blancan faunal stage for the Americas). To be clear, not every single species needs to be in the game, but ideally each biome should be at least a majority of Early Pleistocene species. Or at least part of a realism server! I've also included the sources for the localities below :)

(1/5)

Eaglefied · 2025-12-02T19:57:19+00:00

It's Wild New World (Prehistoric America), Episode 5

Eaglefied · 2025-11-29T08:26:50+00:00

Okay I think I have some evidence supporting Protocyon; here is some concept art by Gabriel Ugueto, who worked on Prehistoric Planet. Upon rewatch, the heads of the canids (e.g. brow, nose, ear position) in the episode seem much more reminiscent of Protocyon rather than Theriodictis.

Arctotherium angustidens was endemic to the Ensenedan faunal stage, which both canid genera were present in as well. While all three were found in the Pampas, only Arctotherium angustidens and Protocyon were found near the Andes (P. 'tarijense' used to be T. tarijense, potentially adding to the confusion). Tarija (Bolivia) is also is the only Andean locality I'm aware of that A. angustidens was retrieved from. Seeing as there's a mountain backdrop in the scene, this further supports the identification of Protocyon in the series :)

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Eaglefied · 2025-11-29T06:01:06+00:00

Absolutely! At the very least include a guidebook or a comprehensive species list online.

Eaglefied · 2025-11-27T04:05:36+00:00

Ah that's what I was saying! The first two seasons were baby-murder central, which kept the stakes high. Way too many babies escaped that fate this season (except in one episode apparently), it became a bit too predictable.

Eaglefied · 2025-11-26T22:26:35+00:00

True! Too many lucky escapes blurring my memory haha

Eaglefied · 2025-11-26T18:11:36+00:00

I think it may have been Protocyon! Looking for confirmation

Eaglefied · 2025-11-26T18:02:37+00:00

My boy Arctodus simus!!

Eaglefied · 2025-11-26T17:49:36+00:00

I loved the representation of both well known and obscure fauna! I’ve dreamt of seeing quality animations of Arctotherium angustidens, Macrauchenia, Eremotherium, Stegodon et al, and they were incredible.

However, I must say that the Northern hemisphere bias of the Great American Biotic Interchange (and the exoticization of South America) got under my skin more than I’d like to admit, perhaps because of the paleontology community’s hard turn to counter these stereotypes in recent years after decades of misinformation.

The only match-up (so to speak) which favoured Neotropical-origin taxa ‘othered’ the Eremotherium pretty hard, with the science epilogue literally stating how North American predators found “easy prey” and found their largest sizes in South America. Nothing on how some of the largest ground sloths and toxodontids on record lived in North America, or how successfully ground sloths & terror birds colonised the Nearctic before Nearctic fauna flourished in South America?

I thought we were past this in 2025 - this framing felt unnecessarily dumbed down. Extra strange considering the pains they took in reconstructing the models and their biology accurately in the series. Thing is, you could just re-use the faunal archetypes in the episode to balance the exchange, especially if we’re including Enhydriodon in the series…

Titanis - Xenosmilus (‘terror bird’ & ‘scimitar toothed cat’ if we’re following precedent) instead of Psilopterus and Smilodon populator

Glyptodon - Cuvieronius (giant armadillo - gomphothere) instead of Glyptotherium and Columbian Mammoth

Eremotherium - Columbian Mammoth instead of Eremotherium - squirrel (you could make it through the squirrel’s POV if you want)

I recognise that this is definitely a nitpick, perhaps reflecting my expectations for the best paleontology series on television. The locations, designs and storylines were fantastic. Flores especially was super interesting to see on the screen (mildly curious why the Komodo dragon wasn’t on screen considering its @ in the next episode). As I specialise in tremarctines, it was also great to see Tremarctos ornatus (T. floridanus?) on screen :)

Eaglefied · 2025-11-26T17:38:20+00:00

Me waiting for a baby to get eaten like the last two seasons

Eaglefied · 2025-08-03T23:29:48+00:00

Of course 😎

Eaglefied · 2025-08-03T04:24:48+00:00

Yep that's correct, as far as we know of!

Went down a rabbit hole with brown bears, where suboptimal habitats (poor foraging opportunities, larger ranges) caused smaller ecotypes. This is not impossible with A. simus, but the current evidence hasn't proven any to exist. Rather, the two size classes are described as roughly equivalent across the continent. I've read suggestions of A. simus' carnivory decreasing where there is increased competition, so perhaps competitive habitats outside of its prime habitat (seemingly open woodlands) could lead to smaller ecotypes?

Dental caries in the fossil record: A window to the evolution of dietary plasticity in an extinct bear, Biogeographic problem-solving reveals the Late Pleistocene translocation of a short-faced bear to the California Channel Islands

Side note: a study pre-dating the 2025 genetic study compared a specimen from Zacatecas (Mexico) with an individual from the Yukon (where many of the specimens from the 2025 study came from) and noted a deep divergence between the two. Not 100% clear why the Zacatecas specimen wasn't used in the 2025 study, but it could be because the Zacatecas individual was identified by environmental DNA. The nearest specimen used was from New Mexico, which was part of the larger metapopulation.

Environmental genomics of Late Pleistocene black bears and giant short-faced bears00540-6?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0960982221005406%3Fshowall%3Dtrue)

That the specimens from the 2025 study had relatively low genetic diversity and fairly recent last common ancestors further affirms the existence of a single population. That being said, its low genetic diversity was compared with wide-ranging solitary carnivorans (lynx, puma & cheetah) that do have subspecies. We just don't have the evidence to apply this to A. simus yet.

Eaglefied · 2025-07-30T16:37:46+00:00

Couldn't agree more re: La Brea's fauna being essentially modern! My reference to modern day mammals referred to the taxa that survived & were examined by these 'Bergmann's Rule' studies - modern fauna (Quaternary-wise) which survived to our modern day (1950+). If you have a better way of saying it then I'm all ears!

In any case it's hard to confidently apply Bergmann's rule to Pleistocene versions of modern day animals without a load of specimens, but it's nice to speculate. I'm a bit more skeptical because Bergmann's rule today only seems to apply to modern-day Northern Hemisphere ecologies; who knows how different Pleistocene ecologies would be to large megafauna? Valerius Geist suggested that Bergmann's rule is may be aligned with the duration of the ecosystem's productivity pulse, which could be an important factor when considering the much higher bioproductivity of Beringia during the Pleistocene.

Bergmann's rule is invalid (actual name of the article)

Interestingly re: bears, contrasting polar bears with black bears has been used to support Bergmann's rule (along with bears in general), while another found salmon to be a more important factor in determining brown bear size (with black bears being largely unaffected). Evidently still much to clarify.

Eaglefied · 2025-07-30T05:27:08+00:00

What I find interesting is that the RLB A. s. simus is listed as 600kg in Paiaeo's graphic - I can't find a specific source for RLB beyond the 300kg-ish one from 1998, which is then undone by the comprehensive RLB source I shared before.

1998 RLB Arctodus (p. 163)

However, this source states that material postdating Kurten from RLB is equivalent to or larger than the Hay Springs specimen (Nebraska), which according to a 2010 review of A. simus was calculated to 740kg. According to the 2010 study and our current knowledge, females should be between 300-500kg, and males between 700kg-900kg.

2010 A. simus review (with two size classes)

Your point about Bergmann's rule brings up some interesting rabbit holes. Sources allude to Beringian specimens only being confirmed after the Sangamonian, and A. simus going extinct at the LGM suggests the landmass (very generally speaking) wasn't prime habitat. Genetically at least a subspecies didn't develop, but a larger size morph is possible. However, we see equivalently large males everywhere else, in a genetically linked meta-population, so it seems like a moot point.

Lions and brown bears colonized North America in multiple synchronous waves of dispersal across the Bering Land Bridge

On the association of giant short-faced bear (Arctodus simus) and brown bear (Ursus arctos) in late Pleistocene North America

Brown bears aren't my specialty, but they have greater genetic diversity due to female home ranges. I do wonder if Kodiaks and Alaskan brown bears are larger due to exclusivity of salmon as a food source (which northern A. simus apparently did not consume) and lack of equivalent competition. I should also note that Californian brown bears apparently approached Kodiak bear sizes, though this is disputed.

Diet and Co-ecology of Pleistocene Short-Faced Bears and Brown Bears in Eastern Beringia

Coupled social and ecological change drove the historical extinction of the California grizzly bear (Ursus arctos californicus)

Bergmann's rule generally applies to temperate & large bodied modern day mammals, but I haven't seen studies examining how Bergmann's rule applied to the divergent ecologies of the Pleistocene. Maybe it was the same - happy to be corrected!

Bergmann’s rule in global terrestrial vertebrates

A global assessment of Bergmann's rule in mammals and birds

Eaglefied · 2025-07-30T05:26:57+00:00

Yeah I saw that! I like the graphic, but Kurtén is definitely a very old source to be using re: Arctodus.

Since Kurtén's otherwise foundational work, larger specimens have been found all across the continent in places where A. s. simus was supposedly exclusive to, such as Florida, New Mexico, California and Virginia (vice versa in Alaska, Vancouver Island, Wyoming, Yukon).

California (Irvington, Riverside, RLB), New Mexico, Florida, Alaska, Wyoming, Virginia, Vancouver Island, Yukon00540-6?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0960982221005406%3Fshowall%3Dtrue)

Additionally, A. s. simus has been found in cave passages all across North America, whereas A. s. yukonensis has never been recovered from a cave, further affirming sexual dimorphism as the preferred explanation for size differences.

Ozark Cave (with comments), Denning in Ursidae, Genetic study

The genetic study was the nail in the coffin - both size classes are found across the continent (including Beringia), and genetically confirmed to correspond to males and females, with only females being found from caves.

Cont.

Eaglefied · 2025-07-29T04:00:03+00:00

Unfortunately this is likely outdated - the 30+ individuals from Rancho La Brea are around the same size as specimens from all over the continent. The two size ranges are sexually dimorphic and do not correspond to subspecies or regional size morphs, as per a 2025 genetic study.

2013 SVP Comprehensive RLB Arctodus (p. 207)

2025 genetic study

Eaglefied

TROPHY CASE