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

learn more… | top users | synonyms

22
votes
5answers
2k views

Why are there species instead of a continuum of various animals?

As I understand it, various animal traits have to evolve gradually, but what happens to the species that are "neither here nor there"? To put it differently, if a species evolved from another, it did ...
5
votes
1answer
363 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?
1
vote
1answer
88 views

How prominent is the gene-centric view of evolution among professional researchers?

Richard Dawkins famously advocated a gene-centric (as opposed to organism-centric) viewpoint on natural selection, most notably in The Extended Phenotype. However, I have also heard "on the grapevine" ...
3
votes
2answers
3k views

Is there any complex organism that is both autotroph and heterotroph?

Possibility also include "adaptation mode" if such exist. I don't discern whether autotrophic/heterotrophic part play only minor role either.
3
votes
3answers
799 views

What is the difference between eugenics and evolution by natural selection?

So with the working definition of Eugenics: "the aim to improve the human gene pool". What are key features that distinguish Eugenics from evolution by natural selection? I mean, besides that natural ...
7
votes
4answers
614 views

Are there any scientifically based predictions or theories of future human evolution?

Reading this question of the stack exchange got me thinking. I believe human evolution is an ongoing process and will not stop. Are there any predictions/theories about the phenotypes and genotypes of ...
1
vote
1answer
58 views

Are there multicellular isogamous species?

Are there multicellular isogamous species? Seeking through the examples of wikipedia I would tend to think that there are no multicellular isogamous species.
5
votes
2answers
170 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 ...
10
votes
3answers
795 views

The evolutionary process in bird wings, especially with regard to winglets

In this answer on aviation.SE a comparison is made between the shapes of airplanes wings and the shapes of birds wings. It concludes with the following remark: After all, no bird has winglets. Not ...
2
votes
1answer
1k views

Why do humans bury their dead?

As far as we know Ape Men or the Neanderthal Man was the first to bury its dead. My question is why. I don't think they practiced religion or believed in spirits or faith or stuff like that. ...
2
votes
1answer
40 views

Somatic Mutations in meristem tissue in plants

In angiosperm, in which layer of the meristem does a new mitotic mutation occurring has chance to be found in a pollen grain or in an ovule? I also welcome some insights about non-angiosperm plants.
2
votes
0answers
50 views

Ancestral states of sex determination system

Most (maybe all?) species that reproduce sexually have either genders (anisogamy) or mating types (isogamy). There exist today many different type of sexual determination system. There is a whole ...
3
votes
0answers
80 views

Understanding the meaning of $s$ and $t$ in a population genetics equation

Sewall Wright in this article (1937) at the end of page 313 gives the equation: $$\Delta q = (s+tq)q(1-q) \space\space\space\space\space\space\space\space\space(1)$$ This equation is an ...
2
votes
0answers
77 views

Does the Jungian notion of collective unconsciousness have any legitimacy in the light of modern neurobiology and epigenetics?

Carl Jung has long ago proposed a rather controversial notion of collective unconsciousness [1, 2, 3], a form of the unconscious (that part of the mind containing memories and impulses of which ...
1
vote
1answer
41 views

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 ...
9
votes
3answers
2k 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 ...
4
votes
2answers
328 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 ...
6
votes
1answer
126 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 = ...
2
votes
0answers
35 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 ...
1
vote
1answer
99 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 ...
7
votes
1answer
108 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 ...
7
votes
1answer
190 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?
11
votes
7answers
4k 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 ...
1
vote
2answers
163 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 ...
3
votes
0answers
86 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 ...
0
votes
1answer
103 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 ...
11
votes
1answer
214 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 ...
2
votes
2answers
142 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 ...
17
votes
2answers
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 ...
4
votes
1answer
395 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 ...
1
vote
0answers
24 views

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 ...
3
votes
1answer
161 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 ...
9
votes
2answers
856 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.
4
votes
1answer
2k 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 ...
0
votes
0answers
31 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 ...
16
votes
5answers
1k views

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 ...
2
votes
2answers
137 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 ...
2
votes
0answers
75 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 ...
7
votes
1answer
498 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 ...
4
votes
1answer
80 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 ...
3
votes
0answers
18 views

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 ...
7
votes
2answers
194 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 ...
10
votes
3answers
208 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 ...
16
votes
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 ...
2
votes
0answers
51 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 ...
1
vote
0answers
51 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 ...
0
votes
1answer
35 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 ...
1
vote
1answer
73 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 ...
1
vote
1answer
116 views

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

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 ...
2
votes
1answer
98 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. ...