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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Gene duplication and subfunctionalization

I’ve been intrigued by gene duplication and want to learn more about it. I’ve read the following from here: several studies suggest that the proportion of duplicated genes retained in ...
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3answers
868 views

Why did abiogenesis only happen once?

If the "primordial soup" theory of abiogenesis is to be believed, self-reproducing organisms spontaneously arose on Earth at least 3.5 billion years ago, surprisingly soon after the Earth cooled down ...
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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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99 views

Effects of selection on effective population size

Background The effective population size ($N_e$) is a central concept of evolutionary biology and is influenced by several parameters. For example: sex ratio bias affects $N_e$ $\left(N_e = ...
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120 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 ...
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4k views

Why do plants have green leaves and not red?

I know plants are green due to chlorophyll. Surely it would be more beneficial for plants to be red than green as by being green they reflect green light and do not absorb it even though green light ...
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How many traits can a multivariate breeders equation handle?

The multivariate breeders equation (MBE) by Lande predicts the change in a trait $\Delta \bar z$ (response) as $\Delta \bar z = G \beta$ where $G$ is a genetic variance-covariance matrix and ...
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26 views

What do we know about the cellular structure, processes, environment, and immediate ancestors of the last universal common ancestor (LUCA)? [closed]

I am up for all scientifically sound speculations, and sources are highly welcome. I've looked into this quite a bit myself via scholar.google, the wiki article, and /r/askscience. I'm really looking ...
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69 views

Evolution, What would the first plants have been like?

I am curious what the first plants are thought to have been like, what they may have evolved from, and how much earlier (or later) than animals they are thought to have moved to land, if they even ...
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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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1answer
43 views

Simplest Biological Organism? [duplicate]

What is the simplest biological organism from which a DNA sample has been or could be obtained? Could the resulting DNA be processed and examined in such a way that the resulting information would ...
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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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7answers
3k views

How did the first self replicating organism come into existence?

When people try to explain evolution, they tell me that evolution is a cumulative result of mutations & natural section of the more superior individuals of a particular species. I think I'm fairly ...
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2answers
126 views

Plants without bacteria? is it theoretically possible?

I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But ...
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46 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 $V_E$ ...
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69 views

At what rate do chromosomal rearrangements occur?

How often does chromosomal rearrangements occur? i.e. what is the rate of chromosomal rearrangements? I am interested about these kind of chromosomal rearrangements that are passed on to the ...
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1answer
39 views

What's the evolutionary reason behind decussation?

A bunch of stuff in the human nervous system decussates. Optical information inputs from the eyes cross over in the optical chiasm. Multiple sensory and motor pathways cross-over before ascending the ...
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131 views

When did CRISPR/Cas9 evolve and what is the likelihood that a superior system for live cell genome editing has already evolved on earth since then?

I've read that CRISPR/Cas9 is currently being implemented and tested for its ability to edit genomes in live cells, and that it is supplanting other genome editing tools in labs, such as TALENs and ...
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4answers
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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7answers
2k views

Is there a biological mechanism for evolution encoded into our DNA?

Throughout high school, I remember learning about Darwin's theory of evolution as if it were near-fact. But something always seemed wrong about the ideas presented. Survival of the fittest Random ...
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2answers
109 views

are the spontaneous generation and evolution the same idea but in a different time scale?

I was in my biology class, learning the history of spontaneous generation and how this idea was discarded. I told my teacher that is the same as evolution but in a different timeline. I Argue that ...
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1k views

Why is 'Grudger' an evolutionary stable strategy?

I am currently reading 'The Selfish Gene' by Richard Dawkins, which I am sure many here have read. The topic are evolutionary stable strategies (ESS) regarding cooperation. I apologise for the long ...
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31 views

Calculate generations since divergence

Can the formula $\mu = k/(2t + 4Ne)$ be used to calculate the divergence time for any two species given a mutation rate, generation time and sequence divergence value?
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232 views

Are wild cats the same species as house cats?

I thought that the definition of species is "can interbreed" From Wikipedia: The wildcat (Felis silvestris) is a small cat found throughout most of Africa, Europe, and southwest and central ...
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Evolutionary reasoning behind redundancy of CST and RuST

According to my neuro-anatomy class, both the Corsticospinal Tract (CST) and the Rubrospinal Tract (RuST) control upper limb movement. What the evolutionary reasoning behind this redundancy and the ...
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144 views

Empirical evidence for Group Selection?

A controversial concept in Biology "Group Selection", has caused confusion and conflict amongst scientists since the since the mid 1990s. The more general realm of study is termed the "unit of ...
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188 views

How is menstruation not suicide in the wild?

Watch any wilderness special for more than a few minutes, and you'll notice a familiar pattern: when a predator catches the scent of blood on the wind, the hunt is on. Wounded animals make the best ...
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817 views

What is the evolutionary explanation for bat's echolocation [closed]

The bat's ability for echolocation is amazing (so are other the abilities of other animals). I was wondering how all of it came to be.
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589 views

Why are men stronger than women?

What are the evolutionary explanations for why women are weaker than men (on average), and is this difference adaptive? See figure one here. I suppose that something puts pressure on men to be ...
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28 views

Why men are stronger than women? [duplicate]

Is there a possibility that human males and females used to have the same strength? That maybe it is because for a long time men have been doing the manual labour and sports and women haven't and ...
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5answers
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Are there any examples of sudden leaps in evolution?

As far as I understand, various abilities like flying, sight, hearing etc. were caused by slow evolution, where those with a greater ability to to these things had better chance of survival. (If this ...
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2answers
105 views

Do couples having children later in life act as an evolutionary mechanism?

Ok, this may be just wild nonsense and I have to warn that my knowledge on the subject is limited. I was reading about how in some countries people choose to have children later in life. After that ...
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0answers
31 views

How likely is it that through dog breeding, tail-wagging has been disassociated with happiness?

I am not a biologist, so sorry to anybody for misinformation in this post. If I understand correctly, dogs evolved the ability to show emotions through various sounds and tail-wagging in order to ...
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2answers
2k views

How and why did mammals go back to the oceans?

If I understand evolutionary biology correctly, mammals first evolved on land as small, rodent-like creatures, in a time when reptiles were dominant on land. Eventually, they diversified into the ...
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188 views

Fisher's Geometric Model for Dummies

Fisher's geometric model is still today one of the most important and fundamental model in evolutionary biology but it seems to me that most student in evolutionary biology don't really understand it ...
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44 views

Definition of “structural underdominance”?

In Stathos and Fishman (2014), the authors refer to the concept of structural underdominance. The first time they mention it is in the first paragraph of the second page (left column) and the term is ...
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4answers
1k views

Why would a single celled organism evolve to be multi-celled?

I read a story this week on Richard Lenski who has been 'evolving' E. coli for more than 50,000 generations now. One comment I read was from someone who doesn't accept Evolution who pointed out that ...
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0answers
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Evolutionary motivation behind number of neurons in DCMMP

I'm studying neuro-anatomy right now and I was surprised to learn that there are only three neurons along the Dorsal Column Medial Lemniscal Pathway (DMLP) which relays mechanical sensations from the ...
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112 views

Why does botulinum toxin seem to be more dangerous to humans than to other mammals?

Various mammals seem to get away with eating parts of carcasses that we would prefer to not even touch, and that we assume will make us sick. Because of that, I assume botulinum toxin is more ...
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141 views

Why is green fur not a thing?

In most biomes on earth, and certainly in the most densely-populated, the best camouflage color or pattern for an animal would be a variant of green, so as to blend in with the leaves and grasses of ...
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2answers
4k views

How many humans have been in my lineage? Is it almost the same for every human currently living?

If I were to count my father, my grandfather, my great-grandfather, and so on up till, say chimps, or the most common ancestor, or whatever that suits the more accurate answer, how many humans would ...
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0answers
19 views

Mutation-drift equilibrium and among loci variance in heterozygosity

At mutation-drift balance, the increased heterozygosity brought by new mutations is exactly equal to the loss of heterozygosity due to genetic drift. At equilibrium, the expected heterozygosity for a ...
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34 views

Why do spiders have a leaf at the bottom of a piece of web?

I've lately seen a lot of instances where a leaf is dangling from a piece of web coming down off a tree. What purpose/s does this serve for the spider? Is it some sort of mechanism for the spider to ...
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1answer
125 views

Why isn't RH disease present in other mammals?

Basically, I have read about RH disease, Its rare but it can happen when an RH + baby is conceived by an RH - mother. This raises many questions. I have heard this problem only happens with humans, ...
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28 views

Regarding inherited fertility in animals

If an animal is fertile does it follow that both its parents of the same species (not necessarily the same species of the offspring)? Was it Mayer who said a fertile male and fertile female of two ...
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1answer
37 views

Evolutionary support for parenting book “The happiest baby on the block”

The book by Dr Harvey Karp (MD) The Happiest Baby on the Block proposes that the duration of human gestation has evolved as a tradeoff between cranial size and development of the infant. He ...
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1answer
60 views

Can we influence evolution by teaching primates to control fire? Should we?

Most people with a strong interest in biology will have heard of Kanzi the Bonobo, the ape that has the wherewithal to collect fuel for a campfire and play pac-man. But is it conceivable to influence ...
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1answer
76 views

How closely related are two parasites Giardia intestinalis and Trichomonas vaginalis?

How closely related (from the evolutional point of view) are parasites Giardia intestinalis and Trichomonas vaginalis? Giardia genome is about 12 Mb and its major cellular proceses are rather simple. ...
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1answer
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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1answer
84 views

Why do baby mammals tend to play?

Why do babies of any mammal tend to play ? From humans to small dog pups, cubs of a lion, baby bears, etc. *I am not sure if the tag I chose is correct or not. Please correct me if I'm wrong.