Changes in the heritable attributes of populations of organisms over time. The mechanisms of evolution are mutation, migration, drift, and selection.

learn more… | top users | synonyms

1
vote
1answer
49 views

What's the difference between evolution fitness and reproductive success?

What's the difference biological fitness and reproductive success in the biological terminology?
5
votes
1answer
216 views

Was Darwin aware of the difficulties behind the concept of species?

Introduction The concept of species is a very old concept that suffers from not being a natural category. There exists no single definition that would categorize living beings into groups and that ...
3
votes
0answers
40 views

Is diarrhoea advantageous to the microbe?

Diarrhoea is a common side effect of many feco-orally transmitted bacterial infections. How does diarrhoea help the pathogen? Should it not have a selective evolutionary advantage? Do all symptoms of ...
2
votes
1answer
52 views

Is the birds' decision to fly away congenital or learned behaviour?

I see two possibilities how could the birds know what to do every fall: The birds' migrations are driven entirely by the vertical memetics and today it is just a custom transferred from parents to ...
1
vote
1answer
54 views

Why is the probability of fixation of an allele equal to its frequency?

Introduction In a panmictic population, the probability of fixation of an allele at a neutral locus is equal to its frequency at that time. I will refer to this probability of fixation as calculated ...
0
votes
1answer
35 views

A doubt on Introgression

Wikipedia says that Introgression, also known as introgressive hybridization, in genetics is the movement of a gene (gene flow) from one species into the gene pool of another by the repeated ...
3
votes
2answers
511 views

Key points of Wagner's theory of innovation

What are the key points of Andreas Wagner's "theory of innovation" from his book The Origins of Evolutionary Innovations? Specifically: What is new in his theory? What problems in evolutionary ...
-2
votes
1answer
185 views

Approaches towards a theory of innovation in evolution

Evolutionary biologist Andreas Wagner writes in his book "The Origins of Evolutionary Innovations: A Theory of Transformative Change in Living Systems" (Oxford University Press, 2011): We are ...
2
votes
2answers
72 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 ...
1
vote
1answer
24 views

Measuring tumor heterogeneity [closed]

I would like to ask if there's any method (established or not) in order to quantify heterogeneity found in mutations occuring in primary neoplasms and metastatic lesions (either common or private) and ...
0
votes
1answer
94 views

Did toads evolve from frogs?

I know frogs still exist but that doesn't mean there wasn't ever a frog population that evolved into toads. Did frogs evolve into toads because their available swamp slowly went away and toads could ...
3
votes
2answers
81 views

Why does the gc content deviate from 50% in prokaryotes

I have read quite some articles but I can't figure out the main reason for gc content deviation in prokaryotes. In eukaryotes I can understand it, because the genome isn't composed at random, like ...
2
votes
1answer
62 views

First life forms to evolve controlled flight

What was the first living organism able to fly in the skies and control their direction , not just Aeroplankton like bacteria and viruses carried by the winds but something like an winged insect or ...
1
vote
1answer
44 views

How to compare diversity between different ecosystems?

I've used the Shannon Wiener Diversity Index for a single ecosystem (species as categorical variables). Do you know any alternative indices, especially ones that compare diversity between different ...
0
votes
0answers
46 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 ...
0
votes
3answers
228 views

How scientists can be confident that human embryo tail is really a tail?

From Wikipedia: Human embryos have a tail that measures about one-sixth of the size of the embryo itself. As the embryo develops into a fetus, the tail is absorbed by the growing body. How are ...
4
votes
0answers
26 views

How were (many) dinosaurs' brains so small?

Brain size (or its proxy, encephalization quotient) usually varies allometrically with mass -- larger creatures need larger brains to control their larger bodies, apparently. Dinosaurs are popularly ...
2
votes
0answers
47 views

Why were dinosaur skeletons so light compared to mammal skeletons?

I was watching a presentation by Dr. Jessica Theodor [1] who discusses (at 38:10), among other things, the skeletal structure of dinosaurs vs. mammals. "Dinosaurs have way lighter skeletons, which ...
3
votes
0answers
51 views

Is $F_{ST}$ a probability and a correlation coefficient?

$F_{ST}$ is one of the most famous and most important statistics of all of evolutionary biology. Yet, many people misunderstand it or misuse the classical results from the literature on $F_{ST}$ (...
0
votes
1answer
37 views

the evolution of the human brain size [closed]

I was thinking, as I know, sometimes the process of producing DNA did not work well(correct me if I'm wrong), so it gives us some changes in the object we gonna ...
1
vote
0answers
79 views

Does cancer cells come from same process as evolution? [duplicate]

Here is how I understand it: DNA replication is not 100% perfect and error can happen, this error can be good(evolution) or bad(cancer properties). But its not the only source of cancer cells - DNA ...
4
votes
1answer
129 views

Why does evolution only involve heritable traits?

If natural selection favors a certain behavior that is learnt, then wouldn’t that behavior be found more often among a population (as more offspring will learn that behavior from their parents or ...
0
votes
0answers
77 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 ...
1
vote
1answer
41 views

Is there any evidence that any other species are “pre-intelligence”? [closed]

Is there any evidence regarding whether other species might, given time, evolve intelligence as humans have? I realize "intelligence" is a vague word here, but I'm interested in throwing a wide net, ...
4
votes
1answer
39 views

Does the species of snake that eats Amphidromous inversus have chiral dimorphism?

From what I read at Schilthuizen and Davison (2005), Amphidromous inversus is a species of snail that occurs in 2 forms that are nearly mirror images of each other occurring in nearly equal ...
2
votes
0answers
25 views

Describing trait evolution across a very small phylogenetic tree [closed]

I am very new to phylogenetic comparative methods but I want to explore the evolutionary patterns of a number of quantitative traits I have across a small sample (5) of closely related species (...
1
vote
0answers
42 views

Origin of aerobic respiration [closed]

Since life originated in water, did the first eukaryotic organisms utilize the dissolved oxygen in the water or they respired anaerobically?
52
votes
2answers
8k views

What is the evolutionary advantage of red-green color blindness?

Red-green colorblindness seems to make it harder for a hunter-gatherer to see whether a fruit is ripe and thus worth picking. Is there a reason why selection hasn't completely removed red-green ...
5
votes
0answers
41 views

How much of the genetic differences between humans and chimpanzees are due to genetic drift?

Both natural selection and genetic drift play a part in changing our DNA over time. Are there trustworthy estimates how much of the differences over the whole genome between us and chimpanzees are due ...
7
votes
1answer
128 views

Why do fetuses have membranes between fingers and toes?

Are the membranes present between the fetal fingers and toes a remainder of the phylogenetic evolution, or just a way organs do grow most easily?
2
votes
1answer
54 views

How do I measure genetic distance?

I'm not sure how to measure genetic distance. There seems to be many different equations out there, and all the ones I found are rather old. In my specific problem I want to see if the twist in ...
0
votes
0answers
87 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
vote
1answer
96 views

Why do fruits have to ripen?

It seems like most fruits that we consume undergo some sort of ripening process either before or after they are picked from the vine, tree, etc. I understand that sugars are released during the ...
11
votes
1answer
676 views

Why don't rats have a gallbladder, unlike other rodents?

It has long been known that rats do not have a gallbladder, though other species including humans, monkeys, cows, reptiles, dogs and mice, all have a gallbladder. In this paper from almost 100 years ...
5
votes
3answers
228 views

What is the difference between Founder effect and Bottleneck effect?

Both are examples of genetic drift in which there is a change in the allele frequency when the population size becomes small. What is the difference between the two?
3
votes
2answers
58 views

Current scientific theories for evolution of Cucurbita

I'm attempting to find research on scientific theories surrounding the evolution of certain plants, and am unable to find any footing with respect to a certain genus. In this case, I am researching ...
4
votes
0answers
81 views

Do animals have different taste preferences within the same species?

Humans (especially children...) seem to dislike certain foods or drinks, that other humans seem to like. Common examples are coffee, french cheeses, olives, milk, fish and cabbage. Are there examples ...
1
vote
0answers
33 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 ...
23
votes
5answers
5k views

Why do living fossils like crocodiles remain so constant and not evolve? [duplicate]

Crocodiles have supposedly remained unchanged for millions of years, and several other species are considered as "living fossils". How do such species remain so constant over time given that they will ...
3
votes
2answers
96 views

How to name a case of convergent evolution where the same mutation is involved in both lineages?

Definition of Convergent evolution - from Wikipedia > Convergent Evolution Convergent evolution is the independent evolution of similar features in species of different lineages. Convergent ...
8
votes
1answer
150 views

Can we say the 'goal' of Mullerian mimicry is a 'decrease in the number of sacrificed indivials'?

Can we say that Mullerian mimicry allows two species to decrease their number of sacrifice individuals because: Originally, one species needs to sacrifice some individuals to allow predators to ...
1
vote
0answers
28 views

What are the evolutionary benefits for herbs having beneficial health effects on humans? [duplicate]

There are many types of plants which produce chemicals which can be beneficial in treating human illnesses, or at least alleviate painful symptoms. Why would they do that? Is it just random chance, ...
0
votes
2answers
120 views

Are humans evolving since their first appearance? [duplicate]

Is the evolution a very prolonged progress, or are we going to witness further evolution of the human species? If so, in which direction? Are there any widely predicted changes for humans?
0
votes
1answer
113 views

Why does the Vas Deferens detour over the pubic bone?

I was surprised to learn that the vas deferens detours over the pubic bone instead of taking the obviously more direct path. https://human.biodigital.com/widget?be=u1P&uaid=1ly5V Because I would ...
4
votes
1answer
84 views

Are there examples of selection on males influencing female phenotypes?

I've been studying selection on female body color in a sexually dimorphic species and am intrigued by the possibility that selection on males, whether it be through sexual or natural selection, may ...
3
votes
0answers
61 views

How did dolpins acquire the dorsal fin?

I had been thinking bout atavism when I saw a picture of a dolphin. I had seen it before, but suddenly the dorsal fin startled me. How did this dorsal fin evolve, especially, is it some atavism from ...
1
vote
0answers
53 views

Why are there different species of bacteria?

The usual (high school or intro to bio) explanation for diversification of species comes from multicellular, usually sexually reproducing organisms, and seems to be closely tied to the biological ...
1
vote
1answer
99 views

What's the mechanism or structure responsible for new species genetic code generation? [closed]

I always had this question in mind. I think, If humans find answer to it then we can trigger the next evolution of human specie. What is the mechanism or structure responsible for evolution ? I don't ...
-2
votes
1answer
81 views

Why plants and animals are so different even though they come from the same ancestors?

All the documentaries I have watched, books I have read so far on the starting of life on earth only talk about animals. The very first life form on earth was bacteria. Then evolution took us this far....
1
vote
2answers
112 views

Are human beings evolved to eat meat? [duplicate]

I know humans can cook, and prepare almost anything, but are humans specifically adapted to eat meat. One of my doubts humans are not particularly well adapted to eat meat because they lack canine ...