I’m no expert but I think it’s a mutation that still isn’t universal i.e. there is still a very large lactose-intolerant population in east-asia, which is also reflected in their cuisine.
One more is that some people in the Himalayas (Nepalese, Tibetans, etc.) have some pretty recent adaptations for living at extremely high altitudes where there’s less oxygen. This Wikipedia article has more examples of recent adaptations: en.m.wikipedia.org/wiki/Recent_human_evolution
Another interesting factoid is that Africa has more genetic diversity than the rest of the world. So, don’t sleep on the fact that that Homo sapiens spent more time radiating throughout Africa than radiating out of Africa.
I read the question as a difference of traits rather than whole new traits, if that makes any sense.
So my suggestion was that the strength of sexual dimorphism varies. That is, some ethnicities may have a very significant difference in appearance between sexes, but in other ethnicities the difference would be lessened.
There’s also sickle cell anemia: IIRC it protects against something like the tse-tse fly or mosquito borne illnesses native to parts of the African continent
I believe that it offers a degree of protection against malaria. Or, enough protection that you live long enough to reproduce before dying a terrible, agonizing death.
What was the process of ancient Sumerian experimenting and realizing the potential of this new tool they had on their hands?
“Maybe I can use writing to do such-and-such thing…” and proceeded to do the first ever written snail-mail message, or the first medical or mathematical instructions/textbook, the first poem or essay, etc.
I can almost picture the academic analysis…
“The first character syllable can be read as kah or kuh, while the second character is read as unt, together they make the sound kawnt…”
…and then to register astronomical observations! The birth of science, no less.
And all because every year like clockwork, the Eufrates and Tigris blanketed an area of hundreds of square kilometers with a fresh coat of silt (from the Taurus mountains in modern-day Turkey) that was perfect as a rudimentary but cheap, easy and quick writing medium, pushing the point of a stick into a pancake of soft clay, then leaving it to dry and harden in the sun.
Given a radiative forcing coefficient of ln(new ppm/old ppm)/ln(2)*3.7 W/m**2 I have previously calculated that for every 1kWh of electricity generated from natural gas, an additional 2.2 kWh of heat is dumped into the atmosphere due to greenhouse effect in every year thereafter (for at least 1000 years that the resulting carbon dioxide remains in the air). So while the initial numbers are similar, you have to remember that the heat you generate is a one-time release (that dissipates into space as infrared radiation), but the greenhouse effect remains around in perpetuity, accumulating from year to year. If you are consuming 1kW of fossil electricity on average, after 100 years you are still only generating 1.67kW of heat (1kW from your devices and .67kW from 60% efficient power plant), but you also get an extra 220kW of heat from accumulated greenhouse gas.
I have wondered this question myself, and it does appear that the heat from the fossil/nuclear power itself is negligible over long term compared to the greenhouse effect. At least until you reach a Kardashev type I civilization level and have so many nuclear/fusion reactors that they noticeably raise the global temperature and necessitate special radiators.
Except for the young and the pregnant, we’re all wearing red shirts out here. In nature, most living things are highly disposable.
It’s an uncomfortable truth that is also weirdly comfortable at times. As far as nature is concerned I’m a spear carrier who should have been dead a long time ago…this is all gravy, baby!
When the stinger gets pulled out of the bee, the sac with the venom comes out too, still attached to the singer
Attempts to remove it injects more venom.
The life of the bee is worth less than the increased deterrent to animals attacking the hive.
The life of a handful of bees really isn’t worth much at all to the hive. So even when there’s no longer giant ass bears going after hives, there’s not a lot of pressure for the bee to lose the barb.
Edit:
It’s also important to remember that evolution isn’t just competing against predators/prey. It’s competing against competitors too.
If one hive of bees has barbs and worse stings than the one next to it, the one without barbs is gonna get attacked.
So the barbs don’t have to be enough to convince predators that honey is never worth the sting, just that this honey is more painful to get than that honey.
Overtime the less painful honey may be pushed out of the local ecosystem. At which point it’s just barbed bees, and the cycle might start over again with another way stings are more painful.
I just wanted to add that the worker bees with stingers are dead ends in the lifecycle anyhow. Only the queen will lay eggs and only the drones (stingerless) can mate with her. (Unless the years have really screwed up my memory!)
A young female when given royal jelly triggers it becoming a queen and reproductive organs instead of a stinger.
The males are drones. They have male reproductive organs instead of stingers, and they just hang out and try to bone the queen.
But the worker bees are the ones that actually, you know, do the work.
So that’s why European bees won’t “swarm” someone and all sting them. You get a few warning shots and a chance to retreat, just moving away is enough for it to stop.
Meanwhile, African bees had to deal with shit like honey badgers. And as we’re all aware, the honey badger gives very little fucks about anything.
So they don’t half ass defense, they send out a shit ton of bees that won’t stop until the threat is chased away and keeps running away. If they didn’t the honey badger wouldnt even notice.
Then some genius decided to cross breed the species, and we get “Africanized killer bee” that treat everything they come across as a honey badger.
I wonder if that would sometimes be a desirable trait in farmed bees in areas with a lot of predators or competitors.
Like, the human knows that protection will be required and will suit up accordingly, but the ants, wasps or bears that try to rob the hive will be much less successful.
But they forgot that life finds a way and the hybrids wouldn’t just stay where they put them.
They not only outcompete European hives, they’ll straight up raid and destroy other hives stealing their young.
Because their African half evolved in a resource scarce environment. If they run across other bees they view it as a direct threat on their resources. Pretty sure it also causes them to establish new hives much further away than European bees. Which is why they keep spreading so fast.
I’m just glad no one’s tried to crossbreed honey badgers with wolves to combat the hybrid bees yet.
As for solar panels I think the word you're looking for is "albedo"
Off the top of my head I think it's close to earth's natural albedo anyway. Or even if it is a lower number and more energy/heat is absorbed it's so negligible. Only the tiniest fraction of the earth's surface would be/are covered in panels
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