What drives evolution, climate or competition?

Wallace, Darwin's forgotten "frenemy"

(SciShow) June 29, 2017: Everyone knows the name Charles Darwin, but his lesser known frenemy, Alfred Russel Wallace, was developing a lot of the same ideas around the same time. Hosted by: Hank Green. For 10% off Squarespace: http://squarespace.com/scishow  ---------- Support SciShow by becoming a patron on Patreon: scishow

Homo Floresiensis skull, hominin species analyzed in the study (The Duckworth Laboratory)

.

It's bizarre: humans are competitive like animals

(University of Cambridge via Newsweek) Human evolution might be more "bizarre" than we once thought, according to a new study.

In the past, scientists (anthropologists) believed that hominin evolution was largely driven by changes in climate. But now, research from the University of Cambridge has suggested that competition was, in fact, fundamental to hominin evolution.

Wallace, you were right. - I know, Darwin.

"We have been ignoring the way competition between species has shaped our own evolutionary tree," said lead author Dr. Laura van Holstein, a University of Cambridge biological anthropologist from Clare College.

"The effect of climate on hominin species is only part of the story." Interspecies [not to be confused with intraspecies or between humans] competition is common among most other vertebrates: in any new environment there is an explosion of species evolution as each species adapts to fill a particular niche.

I shoulda killed that Wallace to evolve.

However, once all the niches are filled, competition kicks in and this explosive evolution flatlines. "The pattern we see across many early hominins is similar to all other mammals," van Holstein said. "Speciation rates increase and then flatline, at which point extinction rates start to increase. This suggests that interspecies competition was a major evolutionary factor."

However, when van Holstein studied the evolution of our own genus, Homo, things started to get much more peculiar.

(Biographics) Alfred Russel Wallace: The Forgotten Father of Evolution

"The more species of Homo there were, the higher the rate of speciation," she said. "So when those niches got filled, something drove even more species to emerge. This is almost unparalleled in evolutionary science."

In other words, it appears as if competition between different Homo species actually drove the evolution of even more Homo species — a complete reversal of what we would expect to see based on the evolution of most other vertebrates.

Here's what would happen if ALL humans completely disappeared (Aperture)

COMMENTARY

So Long, Thanks for All Fish

(WQ) Given this breakthrough, we should start having competitive games not (intra) between humans and humans but (inter) between humans and animals. The all-female chicken league can go up against Missourians in worm finding. Bull teams can go up against matadors with horn helmets instead of swords. We can launch Iditarod II, a race where hungry dogs or wolves chase humans across the ice and snow to see who crosses the line first. There can be a surfer versus shark competition in the summers to see who can exclude the other from more waves. Fisherpersons can get out of boats and into the water to have it out with schools of sportfish. We can film a "Survivor Congo" mixed gender social strategy game between bonobos and humans. And we can have an international dolphin versus nerds test of intellect, where we will insist on a handicap for having smaller brains than the sea mammals.

• Pandora Dewan [pronounced dawn?], Newsweek.com via MSN.com, June 11, 2024 ('Bizarre' finding changes the way we think about human evolution); Pat Macpherson, Dhr. Seven, Ashley Wells (eds.), Wisdom Quarterly