Changes in the heritable attributes of populations of organisms over time. Major mechanisms include drift, natural selection, mutation, and gene flow (migration).

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Are there genes in humans from the common ancestor of all organisms?

How long ago can human genes be traced? Are there any genes that go back unchanged to the beginning of life on Earth? And if so, how many?
3
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1answer
157 views

Were there lifeforms before LUCA?

This question got me thinking about something. LUCA is the last universal common ancestor of all current living organisms, which is a very different definition from the first-ever living organism. Is ...
14
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1answer
153 views

Has the human 7-day week had any impact on the evolution of species?

Most (if not all) industrialized countries follow a 7-day work week now, such that we are bound to follow a certain weekly trend in matters such as pollution generation, where to go (e.g. stay in town ...
8
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1answer
870 views

Disadvantages of unihemispheric sleep

Is is well known fact that marine mammals and some birds can sleep with one brain hemisphere at a time, since it's essential for their survival. However, at least in my opinion, such mechanism would ...
2
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1answer
54 views

Biology view on trait variability

In reading the annotated Origin... I have come to the following note by Costa on p. 168: Again, modern biologists would disagree with Darwin's idea that especially well-developed traits vary to a ...
2
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1answer
48 views

Preserved alpha complementation over evolutionary time?

Has the result of alpha-complementation ever happened via mutation through evolutionary time, and been preserved in modern day organisms? In other words, has a functional gene product ever been split ...
2
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1answer
142 views

Can epigenetic changes affect reproductive success?

This is prompted by niallhaslam's answer to this question [Since Darwinian times, has there been any striking/notable effects of evolution on humans?]. A comment by Alan Boyd asks whether epigenetic ...
3
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2answers
2k views

Is there an evolutionary reason for the 5 electron transport complexes in plants and animals?

The electron transport chains of both the light reactions of photosynthesis (in plants) and oxidative phosphorylation (in animals) both contain 5 complexes including ATP synthase, as shown below. ...
4
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3answers
135 views

Since Darwinian times, has there been any striking/notable effects of evolution on humans?

I understand that evolution is constant process that acts on a population in successive generations. Thus, it is obvious that evolution is happening. However, I'm curious as to the stricking examples ...
6
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1answer
143 views

Is it possible to increase lifespan through controlled evolution?

A few years back when I was reading The Selfish Gene by Richard Dawkins, there's this short passage where he theorizes about a way to achieve an increased lifespan through controlled evolution. The ...
5
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1answer
126 views

Why was polyploidy not lethal in certain octodontid rodents?

As discussed in Why is polyploidy lethal for some organisms while for others is not?, polyploidy is normally lethal in mammals. However, two species of Octodontidae (South American rodents), are ...
4
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1answer
267 views

Why did mammals evolve to have two testes?

What makes mammals tend to evolve to have two testes?
3
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2answers
92 views

Have proteins been observed to come into existence through mutations and natural selection?

What is an example of a functional protein that has been observed (in real time) to have come into existence through mutations and natural selection (not through an existing one being made defective). ...
11
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1answer
270 views

How do members of cryptic species know who to mate with?

According to Wikipedia: In biology, a cryptic species complex is a group of species which satisfy the biological definition of species—that is, they are reproductively isolated from each ...
11
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3answers
480 views

Is Behe's experiment (evolving the bacterial flagellum) plausible in the lab?

[Warning: this question is motivated by a prominent proponent of "intelligent design": Prof. Michael Behe. I'm not interested in debating creationism.] According to Wikipedia[1]: In Darwin’s ...
9
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1answer
1k views

Why are some berries poisonous?

In my understanding, the evolutional function of berries is to be eaten and pood out somewhere else, so that the seeds of the plant spread. Is this so? Then why are some berries poisonous?
0
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1answer
192 views

From which ancestor species did humans inherit orgasm?

From what ancestors did humans inherit orgasm? Do fish experience orgasm? Are the male and female orgasm the homologues that can be traced to the time when there was no difference in sex between ...
2
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1answer
51 views

Is vision a vestigial sense for deep ocean species?

Sunlight doesn't penetrate beyond a couple of hundred feet from the surface of the ocean. Species that exist at greater depth probably live in a state of perpetual night; yet from a quick google image ...
11
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1answer
231 views

Evolution of long necks in giraffes

In this question, the OP uses giraffe necks as a supportive example of evolution. Is the mechanism described in this post accurate? At some point, I thought I remember hearing that giraffes did not ...
5
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3answers
1k views

How did butterflies evolve to have eyes on their wings?

Some butterflies, such as the UK native Peacock butterfly (Google Image Search) have markings on their wings that look just like eyes, complete with a white fleck to imitate a convex, transparency ...
5
votes
3answers
180 views

Why don't flies avoid the motorway?

Flies have a short lifespan, therefore evolution should technically happen over a shorter period of time (years). Flies die all the time from getting hit by cars on the motorway. Those flies that ...
11
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2answers
410 views

When did vision evolve for the first time?

Today I wondered what the first organism to evolve vision would have been. I assume that it would have been kind of primitive and basic, but of course extremely innovative and eventually useful to a ...
11
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1answer
753 views

How does evolution produce complex organs

I've been wondering lately how evolution manages to produce complex organs. It is pretty obvious to me how evolution would select some minor traits like size, resistnce to illness or climate. There is ...
4
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1answer
156 views

Why would deers keep crossing a river full of crocodiles while some of them have been killed?

I recently watched a clip on Discovery Channel, where I saw deers crossing a river full of crocodiles, ignoring the fact that some of them would have been killed doing so. What could be an ...
13
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3answers
2k views

When has an organism evolved enough to be called a new species?

Imagine that we take a population of horses, split them in half and place them in completely different environments. The two species will evolve separate from each other and because the environment is ...
3
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7answers
380 views

Introductory books about evolution

This days I read some debates on evolution. That made me more interested to read something reliable on topic - I mean books. I'm christian - although I think it doesn't matter on that topic - and I ...
5
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1answer
115 views

Is extreme cladism a mainstream position in the species debate?

In the philosophy of biology it has been claimed many times that a popular position regarding the question of what species are, among biologists, is cladism. For my current purposes, the defining ...
3
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1answer
315 views

Can parents' learned traits be transmitted genetically?

I am wondering whether a behavioral trait (e.g. fear or stress experienced in the lifetime of the parent) can be transmitted genetically to its offspring? I understand that a behavioral tendency for ...
12
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2answers
341 views

Is there any reason for the variation in mitochondrial DNA size?

As my textbook An Introduction to Genetic Analysis points out, yeast mitochondrial DNA has approximately 78 kb of genetic data, while the human mitochondrial DNA contains 17 kb. Is there any evolution ...
6
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1answer
257 views

Computational/mathematical models for predicting phenotype from genotype

Karr, Sanghvi, et al. (2012) propose a whole-cell computational model for predicting phenotype from genotype in Mycoplasma genitalium. Their model simulates myriad cell processes such as DNA ...
11
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1answer
691 views

Is there an evolutionary advantage to crying when sad?

It seems as though the act of crying when sad does nothing to relieve that sadness. Is there an advantage to crying from an evolutionary perspective, or is it the end result of a different process? ...
6
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1answer
346 views

How and when did a dedicated immune system evolve?

I have recently been doing a lot of research into the interplay between the innate and adaptive immune systems in humans, and mammalian laboratory models. This has led to my reading some interesting ...
10
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2answers
161 views

Is there an “evolutionary species similarity calculator”?

Is there a website where I can input pairs of species and get an "evolutionary similarity score"? E.g. (numbers are completely made up) Input: Chimp and Human, Output: 97% Input: Cat and Human, ...
9
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3answers
1k views

Why does the butterfly have a cocoon stage in its life cycle?

Why does the butterfly have a cocoon stage in its life cycle? It could have simply grown up within the egg/cocoon, and emerged as a butterfly. Instead it is first an egg, then a worm, then a ...
7
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1answer
1k views

Why is the Kakapo more attracted to humans than its own kind?

The Kakapo can be seen in this video by BBC. It is said that the species is strongly sexually attracted to humans. Why could this be the case?
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1answer
276 views

Why hasn't mother nature made us aware of our lizard brain? [closed]

In many personal improvement books I've read, people make a distinction between 2 parts of our brain: the logical brain, dealing with logic, judgement, thinking; what makes Humans different than ...
7
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2answers
127 views

Genetic Models for Natural Selection?

My question is simple: Given that evolution is described by random genetic mutations allowing certain members of a species to gain a reproductive advantage over others that coexist in the particular ...
6
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2answers
7k views

How do archaea relate to eukaryotes and bacteria?

I've read that they all share some genes, internal structure, and behaviour with each other, but with different degrees of overlap depending of what the function is. E.g., archaea have some eukaryotic ...
4
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1answer
65 views

Features in individuals causing high population variation

As I understand it, a population with high variation is something sought after, since it makes the population better equipped to face a dynamic environment. Then, I guess features in an individual ...
23
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4answers
979 views

Why do men have nipples?

I'd be tempted to call nipples in men vestigial, but that suggests they have no modern function. They do have a function, of course, but only in women. So why do men (and all male mammals) have them? ...
3
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1answer
280 views

What are samples of “Outlaw Genes”

I read this in a paper Keller and Ross describe their greenbeard gene as an ‘outlaw’. Admittedly, the comment is only made in passing, but are they correct? In this context an outlaw is ...
5
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1answer
130 views

Homologies to insect wings

All winged vertebrates have wings which are homologous to each other and to the forelimbs of the non-winged vertebrates. But what about insect wings? Are all insect wings homologous, and are there any ...
5
votes
1answer
579 views

How and why did mouth and nasal cavity evolve separate?

My initial objection is that nose filters air, mouth is for eating but is used for breathing also, plus they both are used to create sounds. What is the cause and reason in this case, why do we need ...
29
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3answers
2k views

Why is polyploidy lethal for some organisms while for others is not?

Polyploidy is the multiplication of number of chromosomal sets from 2n to 3n (triploidy), 4n (tetraploidy) and so on. It is quite common in plants, for example many crops like wheat or Brassica forms. ...
9
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1answer
696 views

How does population stability evolve?

The number of individuals constituting a population is called population size. Over time population size does not remain constant, it fluctuates to different extent over generations because of ...
17
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2answers
294 views

What are the major evolutionary pressures for Bioluminescence?

What are the major evolutionary pressures for Bioluminescence?
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1answer
288 views

What animals stop other members of their species from mating and why?

(In particular primates) I know chimps do. Powerful alpha males chimp would beat up omega males that they caught mating. I know gorillas do. Powerful alpha males gorillas would beat up omega males ...
0
votes
1answer
181 views

What is the similarity between how cells organize themselves to form a human and how humans organize themselves to form a society? [closed]

Some things I have gathered. Common properties - individuals - communicate - local view - selfish - specialize - organize - replicate - cooperate - emergence Terminology cell ...
4
votes
1answer
63 views

Productive turnover and generations in the fruit fly

I was reading about the Lenski experiments on the evolution of E. coli bacterium and Dr. Elders's experiments on the evolution of the guppy. These two experiments absolutely fascinated me, and seemed ...
5
votes
2answers
160 views

Are there other mechanisms for mutation besides imperfect DNA replication?

I was reading http://www.askamathematician.com/2012/05/q-is-quantum-randomness-ever-large-enough-to-be-noticed/ and saw: [...] the evolution of entire species can be changed by a single mistake ...