Questions tagged [evolution]
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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Finding genotype/allele frequencies of second generation in Hardy-Weinberg equilibrium given that the recessive allele is deleterious [duplicate]
A population in Hardy-Weinberg equilibrium has p=0.6 and q=0.4, and allele q (recessive) is deleterious. If 25% of heterozygous individuals and 50% of homozygous recessive individuals die before ...
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Compare and contrast biological species concept and phylogenetic species concept [on hold]
This is for 10 marks as a homework question
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Epigenetic experiment（Improvement of Weismann mouse experiment） [on hold]
The first phase of the experiment is an improved version of the Wisman experiment, which is mainly used to identify the right and wrong of Wisman and its opponents.
Experiment procedure
Start ...
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1answer
84 views
Evolution of the haplo-diplontic life cycle
From wikipedia > Biological Life Cycle:
haplontic life cycle - the haploid stage is multicellular and the diploid stage is a single cell, meiosis is "zygotic".
diplontic life cycle - the diploid ...
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What was the cause of some egg-laying animals evolution to animal-laying?
Is there a specific reason for this evolution? Are no egg-laying animals more complex beings so their embryonic development requires more time and better nutrition conditions?
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What are some examples of group Species where Alpha Males dominate sexual reproduction at greater rates than do chimpanzee alphas?
Chimpanzee alphas are well known to be forced to form coalitions with beta-males who in return are allowed access to females. The alpha still mates the most, but the betas also enjoy significant ...
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Non-hair synapsid integument
Anybody noticed that mammal skin (both with hair and without hair) has an irregular scaly pattern when seen up really close? If so, may it have been retained from its pelycosaur and even reptiliomorph ...
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What’s the evolutionary benefit of cats playing with their prey?
I just saw a cat playing and teasing a wounded bird for minutes, and I immediately started to wonder what the evolutionary rationale were. After all, it seems eating the prey as soon as possible ...
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Any arthropod with non-sprawling limbs?
Are there arthropods with semi-erect or erect limbs? If not, could it be because of interference between more than four limbs or any other constraint?
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Why do we find flowers attractive?
Given that we (humans) are not evolutionarily closely related to bees, why do we find flowers attractive?
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Are formerly endosymbiotic organelles necessary for eukaryotes? If so, why? [closed]
It is widely known that the vast majority of eukaryotes have mitochondria, which are believed to have evolved from endosymbionts. The exceptions use related structures like hydrogenosomes which are ...
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1answer
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What problem does the Dobzhansky-Muller Model resolve?
This page describes the Dobzhansky-Muller model and I can follow the illustration of the split leading to incompatible hybrids.
But at the start of the page the author states "[Dobzhansky and Muller] ...
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Why are worms, centipedes and snakes long?
Some animals have mostly distinct, non-repeating body parts, each performing a particular function. However, some kinds of animals, such as worms, centipedes and snakes, have a long body that appears ...
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Has anyone confirmed Darwin's theory that nectar began as something “injurious” to sap?
In "Origin of Species", Darwin says (I have added bold for emphasis):
Certain plants excrete sweet juice, apparently for the sake of
eliminating something injurious from the sap: this is effected,...
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21 views
Can you find the amount of heterozygotes in a pop. from the phenotypes shown in the pop [duplicate]
I know the hardy Weinberg equation but that is for the amount of alleles not the amount of phenotypes. So if there are 600 black(dominant) organisms in the population and 400 green(recessive) ...
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Is there any checked case of “involution”?
I know that strictly speaking the term "involution" referring to the evolution theory doesn't hold any meaning. Organisms keep on evolving and changing with time, that's all.
But the following ...
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1answer
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Why do we develop addiction? [duplicate]
Recently, while on the train, I saw a person not holding the handrails on purpose. He decided that playing a game with no outcome whatsoever was more important than his safety. In fact, he bumped into ...
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1answer
37 views
Limbs in synapsids
Within synapsids, there was a change from a lizard-like sprawling posture (like in pelycosaurs) to a more erect stance. Non-eucynodont eutherapsids seem to have had a facultatively erect hindlimb and ...
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1answer
36 views
What species would this be?
A common way to define species can be found on Wikipedia:
A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can ...
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33 views
Why are dolphins born tail first?
I heard most dolphins are born tail first. I have read many explanations from books and internet articles and they said that dolphins are born tail first to prevent them from drowning.
But now I don'...
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21 views
Is it possible to Clone a Dinosaur with a full strand of their DNA? [duplicate]
If you have a full strand of Dinosaur DNA would it be possible to make it living and hatch a dinosaur? Or would it be a failure? Could you use a bird or alligator, for replacein
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15 views
How do crossbreeding with Neanderthals affect the genetic difference between ethnic groups?
I do not know exactly how much Neanderhtal/Denisova DNA non-subsaharan peoples carry around today, but I have heard figures of less than two percent in Europe, up to three percent in East Asia and ...
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1answer
41 views
Why has the human eye evolved to become sensitive only to the visible light? [duplicate]
The human eye has evolved to become sensitive only to visible part of the electromagnetic spectrum. Why? Why is infrared vision disfavoured for us by evolution but not for some other animals? I am not ...
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1answer
24 views
How to define ammonites?
I miss the definition of ammonite. In my opinion, many authors confuse the term "Ammonite" and "Ammonoid". Ammonoids (Ammonoidea) are large group of cephalopods including for example goniatites (...
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Rationale behind Most Recent Common Ancestor (MRCA)?
My main question is this -
I heard Richard Dawkins say in a video that after 1000s of years, any given individual alive today will be either an ancestor to ALL of the humans (in that future time) or ...
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2answers
687 views
Did we evolve from Africans?
I learned about The Theory Of Evolution in middle school and our teachress told us that we evolved from African People. Is that true? How?
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3answers
100 views
How does evolution explain the apparation of different group like: mammals, insects etc
When I am learning about evolution I barely see any source that explains how insects, mammals, reptiles and fish came to be. Can someone show me a source where I can learn about this? Especially ...
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1answer
104 views
Why darwins, a measure of evolutionary change, is calculated on the log scale?
In a famous paper, Haldane is describing the idea of rate of changes in "darwins". Here below is the excerpt where he introduces the math about the concept.
Haldane, J. B. S. 1949. Suggestions as to ...
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1answer
55 views
Did Plant Cells Evolve from Animal, Protist, or Fungal Cells?
I know protists and animals preceded plants but I am unaware of when fungi arose in relation to plants. At the moment, I cannot find a resource stating how plants evolved from existing kingdoms, or ...
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1answer
69 views
Emergence of novel protein interactions by mutation of amino acids
Are there any examples of proteins that, without coming from a recent duplication event, underwent a mutation(s) that caused it to have a novel interaction with a new ligand, substrate, other protein ...
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1answer
56 views
Is DNA from more parents (than two) better for the fitness of the offspring?
I'm designing a system (a computer system actually) and (a whole while ago) I spoke with a friend about it and he had this opinion:
If you combine DNA of more parents (than 2) it's better for the
...
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2answers
332 views
What is the best argument for maximum parsimony method in phylogenetic tree construction?
Beside the fact that maximum parsimony is computationally cheap, what other good arguments are there for it? Is there any model behind this principle? Why would one expect this principle to provide ...
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1answer
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Why are mules/donkeys aggressive when faced with predators but horses are not?
I came upon an interesting quote after going down the rabbit hole on a variety of subjects. While deep in the data, I came upon this quote
oat and farm animal owners likes to have mules with their ...
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1answer
26 views
Increase rate of change in coding regions?
If a sequence is under selection will it acquire more changes over time because of faster fixation than if changes were neutral? Is this true or am I missing something?
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What exactly happens to animals that fail mating rituals?
Quite a few animals (usually males) participate in various mating rituals to showcase their fertility as mates. While presumably, the successful ones get a chance to mate with females, it occurred to ...
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Why do my pets have eyebrow patterns?
I own roborovski hamsters and a duprasi. They both have little white “eyebrows” above their eyes. This is very cute, but I’m not sure what function it serves.
I know humans have eyebrows to try and ...
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4answers
145 views
What's the benefit of the average human body temperature?
Why would the body choose a resting temperature of 36.1c to 37.2c? It seems a very inefficient mechanism of survival considering the typical ambient temperatures on Earth. If there is a benefit to ...
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1answer
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Can anyone help me with these Biology evolutionary properties homework questions? [closed]
my teacher assigned these worksheet questions, they are ungraded, but he said something might come up on the test really similar to this so I really want to get all of them right. I am pretty ...
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Are genes for producing heterozygotic twins sweeping?
The tendency for a woman to ovulate two or more eggs at once, which may results in a heterozygotic multiple births is the way I understand it at least to some part genetic.
At least since the ...
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1answer
67 views
How are the first mammary glands thought to have functioned?
I happened upon a book (not about biology) containing this text:
A life-changing birth occurred on the planet about 190 million years ago [...] the first tiny shrew like creature brought forth an ...
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How many times have Ecdysozoans made the transition to land? [duplicate]
In my evolutionary course we were taught that land plants are a monophyletic group, the transistion to land happened only once.
The same goes for the tetrapods within the vertabrates.
However this ...
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29 views
Are microbial antigens selected against?
Antigens provoke a response from the host immune system. Could selective pressures result in microbes losing their antigens? Has this been observed? Or are antigens typically so important that they ...
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0answers
31 views
Is there a vertical measure of appearance of a genotype over generations?
Is there some kind of a vertical measure of appearance of a genotype $g$ throughout ancestry, i.e. a measure of how many ancestors of $g$ had genotype $g$. Like for example in saying that on average ...
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25 views
Is Wikipedia a good source of taxonomy? [duplicate]
I have been quite interested in biology lately,and I would like to know whether it is a good choice to look up taxonomic information there.
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2answers
156 views
Are Males the main evolutionary tool for production of genetic variation necessary for evolution?
What I'm saying here is just a personal reflection, that might turn to be gravely erroneous, actually I'm asking that because I didn't see it presented elsewhere.
Evolution is propelled by two ...
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1answer
76 views
Can threat to survival increase mutation rates in germline cells?
Can stress that is related to a threat of survival of a population of animals or plants in some environment, like due to hunger, thirst, fear from predators, etc..; results in an increase in average ...
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Is this model of understanding of what's natural selection and what's not, correct? [closed]
Here in this account I just want to make sure, that I've grasped the concept of natural selection as is usually spoken by evolutionary biologists, truly the wording here are non standard and in some ...
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1answer
50 views
Is it trivial to assume a version of Hamilton's rule that applies for numerous generations?
Is it trivial to assume that a version of Hamilton's rule that applies to numerous generations is:
C > rB
C = lineage fitness lost by an actor,
B = lineage fitness gained from the act, and
r = ...
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48 views
The Viceroy Evolution Paradox [duplicate]
The viceroy butterfly generates a toxin compound which make it distasteful to predators. Biologists agree that the viceroy must have developed this trait as a passive defence mechanism to prevent ...
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3answers
195 views
Are inadvertent environmental catastrophes also examples of natural selection?
I just want to understand the concept of natural selection and its relation to evolution.
Evolution by natural selection occurs when we have hereditary trait(s) that causes an effect on reproduction ...
