What Happened To The Other Eight Human Species?

There were at least nine kinds of human on this planet. Every one of them is gone except yours. One-on-one, we were the weaker species. A Neanderthal had thicker bones, more muscle, and a body built for putting a spear into something the size of a van by hand. Their brains were bigger than ours — on average a Neanderthal skull holds more brain than yours does. They came through every ice age. Then we showed up, and within a few thousand years they were gone. This is about the thing that actually did it, which never fossilised: the metre-tall people on Flores who hunted dwarf elephants, a whole species discovered from one girl's pinky bone, the lion-headed figure someone carved out of mammoth ivory during an ice age when every hour of daylight was food or firewood, and the reason a stranger who believes what you believe is worth more than forty relatives. It ends somewhere you might not expect. The others didn't all vanish. Chapters 0:00 Every face in every crowd 1:04 The people the size of a kitchen counter 1:36 A species found in one finger bone 2:03 Two hundred thousand winters 2:28 Then we arrived 3:30 The problem with the murder theory 3:55 The bigger brain 4:11 The weapon that never fossilised 4:54 The lion-man 6:19 The twist in the case 6:58 We folded them in 7:29 So why yours? 8:11 Still more than one Sources The nine-species framing follows Longrich, "Were other humans the first victims of the sixth mass extinction?", The Conversation, 2019. Neanderthals disappear around 40,000 years ago, with a sapiens overlap in Europe of roughly 2,600–5,400 years: Higham et al., Nature 512, 2014. The video says "maybe five thousand years" and flags that the dates are argued over. The Neanderthal genome and the 1–2% carried by present-day non-Africans: Green et al., Science 328, 2010; Prüfer et al., Science 358, 2017. Denisovans from a phalanx at Denisova Cave, and the several percent more carried in Papua New Guinea: Krause et al., Nature 464, 2010; Reich et al., Nature 468, 2010. The Tibetan altitude gene is Denisovan EPAS1: Huerta-Sánchez et al., Nature 512, 2014. Neanderthal immune-gene introgression: Abi-Rached et al., Science 334, 2011; Dannemann, Andrés & Kelso, AJHG 98, 2016. Small, closely related Neanderthal communities: Skov et al., Nature 610, 2022 (Chagyrskaya Cave). Homo floresiensis on Flores until about 50,000 years ago: Sutikna et al., Nature 532, 2016. Birch-tar glue: Mazza et al., JAS 33, 2006. Eagle-claw ornaments: Radovčić et al., PLOS ONE 10, 2015. Care for a badly injured man: Trinkaus & Villotte on Shanidar 1, PLOS ONE, 2017. The Löwenmensch of Hohlenstein-Stadel is about 40,000 years old, carved from mammoth ivory; replication carving with period tools has been estimated at several hundred hours (Wulf Hein's experiment ran to roughly 400): Kind et al. and the Ulm Museum documentation, 2014. Homo erectus ran from about 1.9 million years ago to somewhere between 117,000 and 108,000 years ago: Rizal et al., Nature 577, 2020. Long-distance shell transfer in the Upper Palaeolithic: Taborin, 1993; Bar-Yosef Mayer, J. Archaeol. Res., 2024. Australia is reached around 65,000 years ago — Clarkson et al., Nature 547, 2017 — a date the video deliberately doesn't put a number on. Three claims are softer than the rest, and the script says so out loud rather than in a footnote. The ~150 ceiling on how many people a brain can really know is Dunbar, Behavioral and Brain Sciences 16, 1993, and the exact number is contested — the video says "somewhere around a hundred and fifty". Shared fiction as the thing that broke that ceiling is an interpretive argument popularised by Harari, Sapiens (2011), not a measured finding; it's spoken as a mechanism with an artefact attached. And "the species that first tamed fire" is the common attribution for Homo erectus (Berna et al., PNAS 109, 2012, Wonderwerk Cave), not a settled fact — it's used as a passing epithet, not a date.