Questions tagged [human-evolution]
The study of evolution with a particular focus on questions about the evolution of modern humans.
196
questions
2
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2answers
258 views
Infer gene frequency within a species over time
I was reading Karlsson et al. (2014) and I came into this:
A selected variant that increases rapidly in frequency in the past ~250,000 years can be detected as an unusual reduction in genetic ...
-2
votes
1answer
96 views
Are women smaller to optimize cloth needs during pregnancy? [closed]
Current life events made me wonder: Is it possible that female humans evolved to be on average smaller than males, so that they can reuse their partner's cloth during pregnancy?
At least in my ...
6
votes
1answer
111 views
Why is there no symmetry in pigmentation when comparing people north and south of the equator?
If you are at the equator and start moving north, the further you travel, the lighter the skin of the indigenous peoples. Considering that we live on a ball, why do we not find the same traveling ...
0
votes
1answer
2k views
Brain capacity of Cro-magnon man vs Modern man
Cranial capacity of Cromagnon man was about 1650cc whereas average cranial capacity in modern human is 1450cc.
My question is, why during the course of evolution, a reduction in cranial capacity is ...
1
vote
0answers
137 views
What were the Neanderthal innovations?
At some point the neanderthal and modern human lineages diverged. I'm not sure what exactly their most common recent ancestor was (I see some sources suggesting homo heidelbergensis), but in any case ...
0
votes
0answers
517 views
Is natural selection still at work in humans in the 21st century? [duplicate]
There has been some disussion on this site about some aspects (e.g. evolution of eye sight, or height, or the effect of medicine, or evolution the past $\sim10000$ years). My question is really more ...
1
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0answers
73 views
Why were the earliest humans hunter gatherers instead of fruit eaters living on trees?
How is it that the earliest humans who evolved from primates (who live on trees and mostly eat fruit) became hunter-gatherers (which seems like a harder, more stressful and more dangerous way to find ...
4
votes
0answers
54 views
The evolution of poor eyesight: is there weaker selection in modern humans? [duplicate]
Short question:
Poor eyesight might have been a major impediment to survival and reproduction in early man (say, 100,000 years ago), but, with the advent of agriculture, major cultural changes, and ...
9
votes
1answer
2k views
Why do we blink instead of winking each eye independently?
Question
Why do we blink both eyes at the same time rather than winking each eye as needed?
Why would winking independently be better?
The benefit would be a minor improvement whereby a person ...
3
votes
0answers
102 views
What niche was humanity theorized to fill before we possesd weapons and coordination to hunt & kill large prey?
I'm really interested in evolution, and for a err 'hobbyist' I think I understand a good bit of evolution and adaptation and the role it has played in many species.
However, I feel I'm rather ...
2
votes
1answer
5k views
Why are the genomes of Humans 99.5% the same?
Human's DNA sequence is said to be roughly 99.5% equal. As far as I understand, this means that if I walked up to you and compared our DNA, the sequence of base pairs would be 99.5% the same.
My ...
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votes
1answer
6k views
Why are human immune systems comparatively weaker than other animal immune systems? [closed]
Humans get sick on such a regular basis and animals will hardly ever get sick. Animals are typically exposed to the same pathogens as humans, yet a dog won't have a cold or the flu twice a year, with ...
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votes
1answer
2k views
Are there different species of modern day humans? [duplicate]
I've been watching nature shows on Netflix (Wildest series) and different animals of the same "family" are actually different species.
e.g. Asian elephants vs African elephants. Asian elephants are ...
4
votes
1answer
864 views
Do the claims in this paper have any degree of validity?
The paper The waiting time problem in a model hominin population talks about a problem of waiting time, etc. Is the methodology of this numerical simulation, and the conclusion right or is it wrong?
...
3
votes
3answers
148 views
What is the human species divergence time
How far back along the evolutionary tree do we have to go to find divergence to a completely different species to Hom. sapiens? I don't count Neanderthals because it seems that part of our genome ...
34
votes
7answers
12k views
Is evolution a fact? [closed]
Richard Dawkins in one of his videos says that Evolution is a fact and not just a theory.
He goes on to say that man and chimpanzees both evolve from apes.
Is this correct (Is evolution a fact and ...
0
votes
1answer
579 views
Neanderthal and modern human population sizes
Are there any estimates of both the modern human and Neanderthal population sizes over the last, say, 100 k years? Since "purebread" Neanderthals are extinct, their population has to hit zero; that ...
82
votes
5answers
26k views
How could humans have interbred with Neanderthals if we're a different species?
To be clear, I'm not doubting that homo sapiens and homo neanderthalensis did interbreed: of that much I'm convinced.
Within the past few years I've seen an upcropping of pop-sci articles discussing ...
1
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3answers
443 views
Did we evolve from monkeys?
Since I was young, I always understood that evolution taught that we descended from monkeys (or apes, not too sure a distinction was ever made). However, someone recently told me that this isn't ...
1
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2answers
286 views
How quantitative is the theory of evolution right now? [closed]
We developed complex structures like eyes and brain, whose mechanisms rely on specific species of molecules and relevant chemical reactions. But we did not develop an enhanced night vision, the ...
5
votes
3answers
528 views
Why are there so many different humans yet chimpanzees are just chimpanzees?
There are two species belonging to the Pan genus (Pan troglodytes and Pan paniscus). That's just two.
I mean, humans have changed radically since we split from chimpanzees, we have Australopithecus ...
1
vote
1answer
223 views
What factors cause males to be more common than females in humans, from an evolutionary perspective? [duplicate]
Fisher's principle states that there should be a 1:1 ratio between males and females born on average for a population. However, if you look at birth statistics your find that boys are slightly more ...
1
vote
2answers
180 views
Junk DNA and “random” mutations [closed]
I'm somewhat irritated by "mutation" generally being described as a fully random factor in evolution: pure randomness does not seem like something that can survive in a long evolutionary process.
And ...
2
votes
1answer
124 views
How did people's liking of ceremonies evolve? [closed]
Habitual group activities are prevalent across many animal species, particularly in mammals, especially in primates.
However, I do not see any evolutionary benefit of this. 'Ceremonies' take time, ...
5
votes
1answer
559 views
What was the evolutionary reason for cross lateralization of the brain?
In the human brain the right hemisphere controls the left side of the body and the left hemisphere controls the right side of the body. What led to this development? Why doesn't the left side of the ...
33
votes
2answers
5k views
How do we know the human species arose in Africa?
I have heard (from multiple sources) that the current scientific opinion is that the human species arose in Africa. What are the reasons for this opinion? If possible, simple and non-technical ...
7
votes
1answer
124 views
How does chromosome fusion get fixed in the population?
It's well known that one of human chromosomes is the result of fusion between two chromosomes in a primate ancestor. If we put anthropocentrism aside, it becomes clear that fusion events happened a ...
0
votes
0answers
94 views
Why do human have continuously-growing hair on their head? [duplicate]
Why do hair continuously grow on human heads, while the same doesn't happen on other parts of the human body? Where there are hair, they only usually grow to a fixed length; but they seem to have no ...
7
votes
2answers
1k views
Why cannot there be multiple sources for same species origins?
We often associate Africa as the geographical location of the origin of humans. Why cannot there exist multiple geographic locations of origin (given same environmental conditions)?
The same ...
3
votes
2answers
695 views
Why don't we keep evolving until we are super-human? [duplicate]
Humans (homo sapiens) have been on the earth for thousands of generations, and we have kept evolving throughout that time. Why don't we just keep evolving so that, let's say, we live for an average of ...
9
votes
1answer
4k views
Why some parts of the human body have immune privilege?
Why have the eye and CNS have immune privilege? Why does the body not develop tolerance against their tissue and instead risk their damage in case an accidental immune cell infiltration?
Wiki:
......
4
votes
1answer
386 views
Current Trend in Evolution of Human Intelligence
Up front, I am specifically not interested in philosophical or ethical considerations re Eugenics and related concepts. In an effort to receive a concise answer I'll post a narrowly defined question ...
9
votes
2answers
9k views
Why do people feel pleasure when using roller coasters / centrifuges?
The feeling when using an amusement park unit is usually a pleasure. Why is it not a pain instead?
Are there advantages, from an evolutionary point of view, in loving this potentially dangerous ...
1
vote
3answers
374 views
Why don't half of us have situs inversus?
I don't see any possible evolutionary disadvantage in situs inversus(the condition where major organs are mirrored from their normal positions) when people with situs inversus can have a normal ...
12
votes
2answers
3k views
Why did humans evolved the scratch reflex?
I've been wondering about this for some time, and I can't come to an answer...
Everybody keeps telling me that scratching one's own skin is bad. It damages the epidermis, creates the hazard of ...
-1
votes
1answer
525 views
How far can we go in engineering our own evolution? [closed]
After recently seeing Christopher Nolan's Interstellar and reading Kip Thorne's The Science of Interstellar, I've seriously been reflecting on the challenges mankind faces in becoming space pioneers, ...
3
votes
1answer
2k views
Largest direct ancestor of humans
Going back the genealogical lineage from present humans to the beginning of life, what was the biggest - in terms of body size or mass - animal in this sequence?
More generally, what would a time vs. ...
2
votes
1answer
409 views
Which came first in hominid evolution: language or bipedalism? [closed]
I suspect both language-use and upright-posture have anatomical consequences. So does the fossil record show which came first?
NOTE: To the folks who marked this question "homework": This is ...
4
votes
1answer
339 views
A colony of humans are sent to an alien world, at what point would the descendants evolve to be genetically incompatible with Earth humans? [closed]
I recently heard about the evolution of the London Underground mosquitoes, and how they have changed genetically enough that they almost can no longer reproduce with above ground mosquitos. Since this ...
3
votes
1answer
630 views
Fecundity per woman in early humans
The average fecundity per woman varies a lot from country to country. I call average fecundity per woman the average number of born children per woman. In Homo sapiens, what was the average fecundity ...
4
votes
1answer
538 views
Miscarriage in early humans
Today, about 10 to 20 percent of known pregnancy end in miscarriage. Pregnancy is a biological process that has been very well studied by medicine. As a result, modern medicine helps a lot to prevent ...
7
votes
1answer
666 views
When did our ancestors switch to a menstrual cycle instead of the estrous cycle?
The Wikipedia page on the Estrous cycle says:
Humans have menstrual cycles instead of estrous cycles. They shed their endometrium instead of reabsorbing it. Unlike animals with estrous cycles, ...
2
votes
1answer
5k views
Speciation of humans? [duplicate]
Since we homo sapiens (and all other species) are continuously evolving, are humans undergoing speciation based on our environment? OR has there been any difference across people that could say ...
9
votes
2answers
324 views
How was the resemblance between apes and humans explained in pre-Darwinian biology?
Humans and apes have somewhat obvious similarities, these must have been apparent to natural philosophers before the possibility of a common ancestry was first proposed in the mid-1800's. These ...
23
votes
1answer
7k views
Why do we have five fingers?
Humans (and other humanoid mammals) have five fingers in each hand.
Curious to know, why five? Wouldn't more fingers be more useful?
Is there any evidence that it used to be different and natural ...
5
votes
3answers
432 views
Is there evolution in humans since the first homo sapiens sapiens
Has the human species changed since first defined as homo sapiens sapiens?
I'm asking this question partly because I'm wondering how we might evolve next.
