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 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 ...
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257 views

Why haven't land animals evolved beyond urination?

It occurred to me (while urinating) that this would seem to be selected against because water is a scarce resource. Why are we constantly losing water we don't need to through urination? What is ...
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142 views

Could cancer be in itself a evolutionary process?

Could cancer be in itself a evolutionary process? Maybe in some way could it be a process of variation? Or would this idea be completely without support, if so, why? I don't mean that each case ...
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146 views

Theoretically, is domestication of (virtually) any animal possible?

Looking at ones that manage well alongside us human animals, such as dogs and cats, we see that this is possible for evolved, distant animals to have heritable, preferable traits around people. ...
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236 views

Variations in Genome Sizes

Why is there wide variation in genome size amongst groups of protists, insects, amphibians and plants, but less variation within groups of mammals and reptiles?
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128 views

Is (Brain Mass)/(Total Mass) still considered a valid indicator of intelligence?

I was reading this(1) and it led me back to ask a very basic question (I'm not a neuroscientist). All the way back to undergrad anthropology and neuroscience courses I remember being taught the ...
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248 views

Experimental evidence for the selfish gene vs. the selfish individual

In the Selfish Gene, Dawkins makes the argument that a better view of evolution (i.e. more in accordance with experiment) is obtained if you view the basic unit of evolution to be the gene rather ...
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199 views

What evolutionary pressures pushed Galápagos tortoises to mature so slowly and live so long?

I read that they take up to 40 years (in the wild) to reach the age of reproduction and are thought to live over 100 years, with one in captivity reaching over 170 years. Can someone explain in ...
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98 views

Are fish and reptilian scales homologous?

Wikipedia: Fish scales are dermally derived, specifically in the mesoderm. This fact distinguishes them from reptile scales paleontologically. So aren't reptilia scales also dermally derived?
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272 views

Evolution of umbilical cord and reason of its elongation

To answer a question myself, recently I've read that Years and years ago, a long umbilical cord enabled a woman to grasp her baby after birth and run away from predators" Update: $Question:$ ...
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581 views

Smallest unit on which selection can act

Traditionally, the individual was considered to be the smallest unit on which Natural Selection (NS) acts. Today, we usually consider the gene as being the unit of NS. Of course, we should also ...
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239 views

Ecomorphs as evolutionary definitions

There have been demonstrations of ecomorphs in different taxa, where each morphology type is associated to a single environment. I know that it happens because special morphological characters ...
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167 views

What evolutionary mechanism caused felines to develop purring?

And why can some felines roar while others meow?
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67 views

What is the “Spandrels” debate about?

In a former question, as a side question, I asked a clarification about the "Spandrels" paper. Being not a biologist, it was the first time I encoutered it. Subsequently I tried to collect some ...
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273 views

Empirical evidence for species selection

Do we have any empirical evidence in favor of species (or lineage) selection? Do we know some cases that can only be explained (or seem to be only explained) by lineage selection? What are today the ...
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61 views

Why don't fish groom each other?

Fish are often plagued by external parasites, which are presumably difficult for them to remove. There are well known cases where large fish come to coral reefs and allow smaller fish to pick off ...
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103 views

Simulating substitution rate of neutral mutations

I am trying to computationally simulate a population based on the Wright-Fisher model I would like to get to the classic result of the neutral theory of molecular evolution that the rate of neutral ...
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110 views

Lost Ability to Regenerate Body Parts during the Transition from Amphibians to Mammals

Why have higher-order animals lost the ability to regenerate body parts during evolution? Wouldn't it be better for survival? What is the evolutionary theory behind it?
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What are some examples of evolving networks in biology?

I'm a master student working on networks analysis in general. A network is something that has nodes and there are links between the nodes. Nodes and links could have attributes. An evolving network is ...
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287 views

Correlation between genome size and mutation rate?

Martin Nowak in his book "Evolutionary Dynamics" talks about a given correlation between genome size and mutation rate. What correlation does exactly exist between these two concepts? Is it a ...
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183 views

How to get smallest subtree containing a set of nodes from BioPhylo?

I'm testing out various phylogenetic libraries in Python. I want to read in a Newick tree, then, given a list of taxa, generate the smallest tree that contains them all. This task is quite simple and ...
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146 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 ...
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263 views

What is the benefit for cells having the ATP production regulated in mitochondria compared to being from the nucleus?

Mitochondria have their own DNA and appear to be loosely connected to the nucleus and it role. Why are the functions of mitochondria not in the nucleus? Why doesn't the nucleus control the ...
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42 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 ...
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36 views

Components of the concept of Developmental Noise?

Developmental noise is a concept that correspond to the amount of possible phenotypic variance of a given genotype in a given environment. Intrinsic noise (aka Cellular noise) is a component of ...
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43 views

Is there any evidence telling us what the oxidation state of early earth's atmosphere was?

I ask this question in relation to the origin of life. I realise it would probably be better suited to a geology stack exchange, but it does not yet exist. The Miller-Urey experiment gives a lab ...
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142 views

What selective factors drove the evolution of lactose in lactation?

As far as I can determine, lactose, and the monosaccharide galactose have few biological uses outside of mammalian lactation. It not only required enzymes for its production, but enzymes in offspring ...
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74 views

Gender and age-specific mutation rate in plants

Background General concept According to Cochran and Harpending (2013), mothers transmits on average a number $x$ of new mutations to their offspring. This number $x$ is independent of the age of the ...
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93 views

Viruses: Adaptation to a new host through repeated host jumps

A friend told me, during a 3 minute discussion, that viruses that are endemic in host $A$ and make repeated jumps to host $B$ but can't be transmitted between individuals of species $B$, may slowly ...
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446 views

How would constantly growing nails have aided early human?

Nails grow rapidly and constantly, such that without constant artificial trimming they would reach lengths difficult to manage. How did this benefit early humans, say 200kya? Were they used like ...
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78 views

Why are recombination rates increasing in mammals?

I have recently become fascinated with an awesome topic in biology and evolution that I feel is rarely covered in biology courses. That is, rates of meiotic recombination, or the the amount that an ...
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70 views

Linkage disequilibrium with multiple alleles and loci

Linkage disequilibrium $\left(D\right)$ for two bi-allelic loci is defined as: $$D=X_{11}X_{22} - X_{12}X_{21}$$ where $X_{11},\ X_{12},\ X_{21},\ X_{22}$ are the frequencies of the haplotypes ...
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148 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 ...
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121 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 ...
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41 views

How to define “Quasifixation” in continuous approximation of finite population?

Background Many models including the famous very first models derived by Sir Ronald Fisher in his early career, assume infinite population size. In an infinite population, an allele can rise in ...
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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 ...
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Is the theory of evolution being disproved by bats?

For some species the Darwin's theory evolution makes perfect sense. I can easily imagine how, for example, the giraffe has evolved to its current appearance: the natural selection was favoring ...
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266 views

Biodiversity is restricted by genome combinatorics?

Me and some friends are interested in opinions for the following: Conjecture The maximum number of species must be limited by the maximum combinatorial/permutational space that can be occupied ...
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449 views

Are there any multicellular forms of life which exist without consuming other forms of life in some manner?

The title is the question. If additional specificity is needed I will add clarification here. Are there any multicellular forms of life which exist without requiring the consumption (destruction) of ...
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189 views

How does natural selection favour large body mass and size (or so it seems)

I was walking through a park this afternoon and observed a few birds having fun flying around and it got me thinking why would natural selection favour birds with flesh at all if it hinders their ...
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243 views

Why do farts stink, but perfume does not?

Why is it that natural things like farts, poop, halitosis etc., from which we are always surrounded smell "bad"; whereas manufactured products, such as perfume or glue smell "good" to most of us? In ...
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203 views

Do any birds beside the family Columbidae (or any reptile or mammal) feed their young “Crop Milk”

Birds from the family Columbidae (e.g., doves and pigeons) produce a fatty, milk-like substance in their crop. The secretion is often referred to as "crop milk." They feed crop milk to their young ...
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148 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 ...
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175 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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395 views

What is the viability of Intelligent Design as a supplement to chemical abiogenesis and Darwinian Evolution?

First of all I am not endorsing Intelligent Design (Wikipedia link); I'm asking this because I (someone who does not have a background in biology, organic chemistry, or philosophy) got into a ...
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107 views

What are the atmospheric requirements for large dinosaurs?

What are the atmospheric requirements for large dinosaurs? and are the atmospheric constituents for supporting large dinosaurs any different from the atmosphere today?
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169 views

Good book on Origin of Life [closed]

What is a book that goes into reasonable detail (but isn't textbook-level technical) about the origin of earth and in particular the origin of life on earth? Something intended for a broad audience, ...
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246 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 ...
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268 views

What did pangolin scales evolve from?

Were they developed anew or a heritage from fish?
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553 views

How do I calculate the change in allele frequency in a haploid population under selection?

From this book For simplicity, let us consider a haploid organism and assume that the frequencies of alleles $A_1$ and $A_2$ are given by $x$ and $y=1-x$, respectively. We also assume that the ...