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

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Model for fluctuating selection

Is there any mathematical model to predict the behaviour and long-term consequence of counter-acting selection at different time scale? For example, let's consider the bi-allelic gene A, with alleles ...
3
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1answer
85 views

Mutation Rate in Multicellular Eukaryotes

I always hear people saying that the mutation rate is around $10^{-6}$ or $10^{-7}$. I don't even know if this number is the mutation rate of genes or of a single nucleotides and I actually (almost) ...
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541 views

What does to “evolve” exactly mean? [closed]

In this article, the author says: Evolution isn’t “leading up” to anything, it just drunkenly limps along using the same set of tricks in slightly different orders. On other occasions, however, ...
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460 views

Mutation-Selection-Drift Equilibrium

mutation-selection-drift equilibrium is one of the most important concept of population genetics. I could easily find the calculations for mutation-secltion equilibrium and for mutation-drift ...
4
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1answer
267 views

Why isn't Rh disease present in other mammals?

I have read about Rhesus D Hemolytic Disease of the Newborn, sometimes called "Rh disease". It's rare, but it can happen when an Rh+ baby is conceived by an Rh- mother. This raises many questions. I ...
4
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1answer
237 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 ...
4
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1answer
163 views

How to calculate the effective population size ($N_e$) with overlapping generations?

From this Source: If generations are overlapping, then the effective population size $N_e$ does not equal the population size $N$. I know mathematical formulations in order to find the effective ...
3
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1answer
76 views

Is there any knowledge of physics can be applied in to evolution?

I have asked a similar question in Biology.SE (What physics knowledge can be applied to biology of organisms and ecosystems?), but it just about organisms and ecosystems, not evolution. After watching ...
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2answers
3k views

Can you answer Ray Comfort's question on Biological Evolution? [closed]

https://www.youtube.com/watch?v=U0u3-2CGOMQ There's this video on Youtube about biological Evolution that has gone viral. I'll paste it above for your convenience. To cut to the chase, Ray Comfort ...
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1answer
45 views

Coniferous trees in temperare rain forests

In temperate rainforest, the dominant plant form is often coniferous trees (source). However, coniferous trees are also the dominant plant form in a very different climate and form a different biome ...
2
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1answer
410 views

Why are some fungi poisonous?

There are many poisonous fungi in nature. For example Amanita Phalloides. What reasons could a fungus need poison for? Some species, like venomous snakes, use poison to kill other species as prey. ...
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3answers
209 views

Formation of Life

Originally, life evolved from non-living matter. Why is life only generated from other life nowadays, and why doesn't it evolve from inanimate matter, like it did originally billions of years ago, ...
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2answers
249 views

Phylogenetics and the Tree of Life

As far as I understand, evolution is nowadays pretty much analyzed through phylogenetic trees, that is cladograms. These are constructed using the available records and taking some key structures and ...
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0answers
78 views

How does the population fitness changes after a change in mutation rate

The mean population fitness as given by mutation load theory depends only on the genome-wide mutation rate ($U$). My question is: how many generations is needed to reach a new mutation load ...
7
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1answer
85 views

Hamilton's derivation of direct fitness from his 1970 paper

In his 1970 paper "Selfish and Spiteful Behaviour in an Evolutionary Model", Hamilton uses Price's equation to derive his well-known rule $rb -c >0$. My question is about one of the steps in his ...
20
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1answer
4k 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 ...
4
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4answers
195 views

Are there known examples where an evolved mechanism “echoes” one originally provided by the environment?

Short summary I am a researcher in origins of life, a field that deals with hypotheses about evolutionary processes that took place before LUCA (the last universal common ancestor), and with the ...
6
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1answer
1k views

How did giraffes develop their rete mirabile failsafe?

Giraffes, being one of the tallest mammals in the world, have a failsafe called rete mirabile to prevent them from dying from excessive blood pressure while lowering their head.[1] Due to their long ...
5
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2answers
124 views

Can I force evolution in a group of cells by removing all the smaller cells?

I actually have algae growing in water in a container. I was thinking if it was possible to filter the water so that all the small cells will be filtered out and only the bigger ones will remain to ...
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2answers
270 views

Evolutionary history: did any organs start out as autonomous organisms?

I've read that the cell nucleus was once an autonomous organism that was "enslaved" by the larger cell at the time of the Eukaryotic Revolution. Are there any organs in the human body that we know of ...
3
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1answer
69 views

What is the most recent well-attested common ancestor of chimpanzees and humans?

Humans and chimpanzees are related and thus have a most recent common ancestor. Of course pinning down this precise point is essentially impossible, so I'm interested in close ancestors of this most ...
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4answers
1k views

How come most animals never seem to evolve over millenia?

People often say, including those with extensive knowledge in biology, that a certain species of animal will evolve in one way or another: 1.From changing environments. 2.Mutations. 3.Possibly even ...
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1answer
143 views

Duplicity Vs. Singularity of Mammals Organs [closed]

Are there known evolutionary reasons why mammals contain 2 of some organs (such as lungs and kidneys) and only 1 of some (such as liver)?
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2answers
3k views

What is the evidence that australopithecines were bipedal?

Before the discovery of Australopithecus afarensis in the 1970s, most anthropologists believed that an increase in brain capacity had preceded bipedal locomotion. However, this reconstruction of the ...
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3answers
5k views

What if rB=C in hamilton's rule?

Hamilton's rule states that if rB>C then a gene giving altruistic behaviour will increase in frequency in the population. What would happen if rB=C? Will an individual perform the altruistic act?
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1answer
177 views

The origin of molecular machines

DNA holds genetic information and holds the key to the evolution of living organisms. Transcription and translation mechanisms enable living cells to process information encoded in DNA. To that end, ...
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1answer
93 views

Poisonous plants, animals, mushrooms: is this always a kind of defense?

I wonder whether developing deadly toxins in the organism's body is always or usually a defensive strategy rather than a by-product.
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172 views

The skin color of bonobos

Why is that bonobos skin color on the areas not covered by hair are dark throughout life unlike the chimpanzee?
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40 views

How much difference in genome is enough to prevent interbreeding? [closed]

I am not a biologist. I am a software developer interested in genetic algorithms therefore i am probably talking to biologists who also have a knowledge of genetic algorithms. I need to "breed" ...
13
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1answer
875 views

The Origin of Mitochondria

For a long time I've just accepted, because it is just what everyone told me, that mitochondria became organelles in the cell when they were "engulfed" by another cell which acted like it's host. This ...
5
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1answer
112 views

How does the body “know” how to metabolize foreign substances

As a freshman biochemistry major, I find myself befuddled by our body's ability to perform complex chemical reactions to break down foreign substances. I can see how we would evolve explicit pathways ...
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70 views

How important is the womb's environment?

- Background - Talking about one phenotypic trait, the total phenotypic variance $V_p$ is decomposed into genetic and environmental variance for this trait, represented by the symbols $V_G$ and $V_E$ ...
2
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1answer
1k views

Why were dinosaurs not as smart as we are?

According to http://en.wikipedia.org/wiki/Dinosaur, Dinosaurs were the dominant terrestrial vertebrates for 135 million years. They had a lot of time to evolve. My question is: why were dinosaurs not ...
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3answers
266 views

Evolutionary chronology - if any, which species have evolved in the last 100 years

I heared somewhere, I cannot remember where, that there has not been an evolution observed in our lifetime. In life science class, right at the start, we was doing the usual MRSGREN (how to tell if ...
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3answers
476 views

Are domesticated animals really “more intelligent,” or is that a myth/misunderstanding?

Often do I hear people speaking of how the domestic house cats are more friendly, less ferocious, less savage-like, and smarter and/or than their distinct but equivalent feline-species friends, like ...
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4answers
256 views

Why do some people find vegetables so repellent when evolutionarily they should find them an attractive and thus tasty food?

Why do certain people (especially kids) find vegetables so "repellent" when evolutionarily they should find them an attractive and thus tasty food? I ask this question because if Darwin's theory of ...
8
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3answers
362 views

Evolution: One big population vs. many small populations

Let's say I want to evolve a bacterium that is resistant to an antibiotic. I want to do this by growing initially clonal populations of bacteria in presence of this antibiotic for a long time. I have ...
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1answer
957 views

Deciduous trees in tropical rainforest

Some books says the dominant plant form in tropical rainforest biome is broad leaved evergreen trees. Other books say it is broad leaved evergreen trees and deciduous trees. What is the most accepted ...
6
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1answer
253 views

What percentage of the (additive or not) genetic variance is explained by the 'n'- most important loci?

Standard models in population genetics look up at the evolution of few loci which impact fitness. The variance in fitness is determined by the genetic variance and the environmental variance (and the ...
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0answers
79 views

What are the common methods to estimate additive genetic variance?

Additive genetic variance can be estimated in a number of ways, and is a key concept in evolutionary biology and quantitative genetics. What are the typical methods (experimental designs) used to ...
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1answer
1k views

Why are urban birds still scared of humans?

I understand that animals are naturally scared of humans because we basically slaughtered every living thing we found in our way for millennia. How long does it take for them to genetically 'forget' ...
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1answer
94 views

What is the evolutionary purpose of white spots in nails and how can they be characterised due to Leukonychia? [closed]

Suppose you haven't hit your nails so the white spots are due to Leukonychia. Are the discoloration i.e. the white spots due to lower porosity (less minerals absorbing) or some other factor? I ...
5
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2answers
192 views

What is Environmental Robustness? Is it different from plasticity?

Hansen (2006) in his review uses the concept of environmental robustness independently of the other concepts of robustness (at pages 139 and 140) without defining ...
0
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1answer
79 views

Would humans eventually evolve to fight off fatal diseases if we didn't treat/vaccinate for them? [duplicate]

I am definitely pro vaccination, and the question is a bit morbid because people would die, but assuming that we didn't treat or vaccinate people for fatal diseases such as Ebola or the black death, ...
2
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1answer
386 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 ...
4
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1answer
348 views

Body size, what are the evolutionary trade-offs?

Background Considering just the "Kingdom Animalia" branch of organisms. It is clear that bigger does not necessarily mean better - there is large variation in body size... From the 94 µm long ...
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2answers
193 views

What governs the size of animal bodies?

Million of years ago there lived dinosaurs up to 36 m high. About 10,000 years ago lived Machairodontinae -compared to cats today they were huge. About 400,000 years ago lived Mammuthus trogontherii: ...
3
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1answer
115 views

Inbreeding depression and dominance

From this article, second paragraph of the second page A classic theoretical result is that the mean of a character controlled by a single locus i with two alleles Ai1 and Ai2 is only affected by ...
9
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1answer
258 views

Are there specific features of birds that cats/small predators are attracted to?

I've recently heard a podcast, in which a professor describes one of the theories as to why we like abstract art. In his talk, he mentions an experiment with seagull chicks, in which the seagull ...
4
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2answers
689 views

Why do we have to exhale (or inhale) in order to speak?

Every time we speak, sing, or make any other kind of advanced noise with our throats, we exhale, or to put it that way, blow air through our throats. Why is this required? After all, speakers do not ...