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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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Where can I find a comprehensive delineation of the animal kingdom with all its subclassifications? [duplicate]

Ideally I would like to see a mind map like structure but a linear representation would also be fine. If the periodic table is the touchstone of chemistry where is the biological equivalent and what ...
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1answer
17 views

Can I make an population genetic analysis from incomplete protein?

I have an dataset of fasta sequences. This proteins are not complete (My sequences have 700 nucleotides,while complete sequences have 1725 nucleotides)I would like to know if i can make an population ...
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3answers
3k views

Are mutations a source of genetic variation?

Here is a question from the book SAT II Success Biology E/M (where the SAT is the exam taken by the American high school students): Which of the following statements is true about mutations? (A) ...
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29 views

Why doesn't evolutionary pressure turn common household bugs white? [duplicate]

If household bugs (ants, houseflies, spiders, etc) were white in color instead of black, they would be much harder to spot and hence squish, since they would blend into the white walls of most houses ...
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0answers
36 views

What function will survive evolution?

I wrote the following phrase in my scientific text: X is ubiquitous in life of Y. On some occasions X might be detrimental, resulting, for example, in so so phenomena. But is it plausible that a ...
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0answers
17 views

Cichlid fish in Africa

Are the cichlid fish in Africa an example of divergent or convergent evolution? On the one hand they have evolved similar features to each other indicating convergent evolution, but on the other, they ...
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2answers
85 views

Has evolution made a mistake with prehistoric animals?

Let me start this by saying I have very limited knowledge in biology and evolution. However, when visiting museums and watching documentary movies, I always get impression dinosaurs (and other ...
2
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1answer
17 views

Cross-species infections

I’ve heard that HIV developed from SIV, etc. I’ve also heard that most species (including most monkeys) can’t get a common cold like humans. So then what causes infections to be able to travel ...
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1answer
51 views

How can two biological sequences be anything but homologous?

If we consider homology between two nucleotide sequences as a yes/no answer to whether they have shared a common ancestral sequence, then given that all life share common ancestry and sequences are ...
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1answer
16 views

Genes related to senses and their variation across animals

Animals often have very different numbers of active genes related to any sense. For instance, most fish or even aquatic mammals have very few olfactory receptor genes, whereas this is higher in ...
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2answers
37 views

Mating patterns and genetic superiority

In peacocks and peahens, the peahens prefer mating with peacocks having a large and bright tail. But how is having a large tail an indicator of genetic "fitness" (in survival terms) ? If having a ...
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2answers
25 views

What are the advantages and disadvantages of tree structure having 3 trunks/stems rather than 1

Due to strong wind there is a likely chance that trees might be uprooted. Hence an idea was presented that if the structure of the tree is like the one in this picture the stability of tree might ...
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0answers
19 views

Is it appropriate to say “selection of” or “selection for” an allele that evolves by genetic hitchhiking?

In terms of Sober's selection of/selection for distinction, is it appropriate to say that there was selection of or selection for an allele that evolved by hitchhiking? I am inclined to say selection ...
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0answers
13 views

Coacervater were more like Viruses or Cells?

The answer considers them as first formed living cells as they were precursor of life. But they had no lipid bilayer nor any cellular organization, shouldnt they be more like Viruses ,or like Prions ...
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3answers
41 views

Why are there few tetrapod dinosaur carnivores?

Today, most big carnivores are quadrupeds. Bears, Tigers, wolves. During the Jurassic and the Cretaceous, carnivores were mostly bipedal, dinosaurs mostly from the Therapod family. Why was ...
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0answers
24 views

Is human beings going to evolve again? [duplicate]

We know that man had reach his present form after a billion years evolution. So is there any chance for these human beings to evolve into a new species having much more cerebral capacity and sometimes ...
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1answer
32 views

How can biologists rule out multiple early organisms that went through conjugation?

The current idea is that all life evolved from a single cell. Analysis indicates the probability of two different origins being very unlikely, given shared DNA. However, why couldn't numerous ...
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0answers
15 views

Are cholesterol and phytosterol an example of convergent evolution?

Given the new paper on Dickinsonia http://science.sciencemag.org/content/361/6408/1246 I was wondering: are cholesterol and phytosterol examples of two unrelated molecules where convergent evolution ...
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2answers
60 views

If virus is an inanimate(non-living) structure, why it poses tendency/intelligence to spread itself to others?

A virus has no aim, no agency but just a chemical propagation(DNAs, RNAs). Still, it accounts for millions of deaths and horrible nature. Rabies, for example, is a very deadly disease with a fatality ...
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0answers
32 views

What is the closest relative to odd-toed ungulate?

I have seen about 3 variation of phylogenetic tree about odd-toed ungulate and I don't know which one is really updated or outdated or which one have more backed up theory First is odd-toed ungulate ...
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1answer
30 views

Genotype-Phenotype evolution distinction

I understand the difference between the genotype of an organism and the phenotype of an organism, (genotype being the genetic code, phenotype being the physical expression), however I am unsure about ...
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2answers
157 views

Among primates, is it true that homosexual behavior is extremely unnatural and uncommon?

I was recently reading a book published by some anonymous biologist known as Lynn Saxon, in which she appears to want to refute Christopher Ryan's thesis in Sex at Dawn that prior to the invent of ...
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4answers
182 views

Are there lifeforms that have more than 2 sexes?

Are there any lifeforms on earth that have more than male and female biological sexes? If so, are all three mates required for reproduction or is there something else going on? If not, why not? ...
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1answer
29 views

What is the difference between phyletic and phenotypic gradualism?

As I understand it, Phenotypic gradualism describes the development of new traits as a series of incremental steps. How is Phyletic gradualism different?
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Is there mismatch in injures or death numbers for carnivores that hunt during day time and night time?

Is there significant mismatch in injures or death numbers for hunters (when hunter was killed or injured by its prey), between day time and night time hunts (carnivores that hunt during the day time ...
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1answer
84 views

What makes red meat less healthy than seafood, after millennia of evolving to eat meat? [closed]

We are told that red meat is carcinogen; fish and white meat are not. What make us not "compatible" to red meat after thousands of years of evolution and meat eating, and yet seafood is opposite ?
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2answers
66 views

are there any species that we can identify as being 'mid-way'though an evolutionary change?

I have just learned that dolphins evolved from a dog/cat like land mammal (Mesonix) that became ever-more water venturing. I understand and can visualise how the arms legs and tail slowly evolved into ...
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0answers
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Are cloned spieces significantly more vulnereble to deseases than sexually reproducing species?

I would like to be able to compare the risk for species to go extinct implied by their reproduction mechanism in the very short term. Imagine we choose some species A that can reproduce both sexually ...
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1answer
27 views

Does homology of a trait necessarily imply that the most recent common ancestor had the trait?

If two different species have a trait that is homologous, does this mean that the most recent common ancestor necessarily had the same trait?
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0answers
36 views

Does evolution mean that a species become completely extinct and evolve into another species? [duplicate]

We know it's a fact that animals are rapidly evolving with climate change. So is the polar bear evolving in the North Pole due to warm weather. Does evolution mean a new species of animal evolve ...
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1answer
55 views

Does a reproductively successful male have the same genetics as a reproductively successful female?

Evolutionarily, using humans as an example, it would make sense that a successful female would produce successful male offspring. If a successful female produced male offspring that weren't successful,...
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1answer
62 views

Why do dozens of preys run away from a clearly outnumbered predator? (e.g. zebras and lion)

We are all familiar with scenes where dozens (if not hundreds) of zebras, sheep, or other preys are chased by one lion, one wolf or other predator. Examples are all over youtube, but here is one of ...
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0answers
22 views

Why did the menstrual cycle evolve to be a wasteful process? [duplicate]

Why did primates evolve its menstrual cycle to be such a wasteful process;Why did not a more efficient system develop which did not waste the resource in this manner?
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37 views

Bird vs Fish Encounter?

Visiting a beach at the ocean, I recently saw a Great Blue Heron dive and catch quite a spiky/large (and colorful! I think it was called a sculpin) crosswise in it's bill. It appeared, potential meal ...
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3answers
70 views

Is existence of different alleles for a gene a result of mutation?

I would like to understand evolution. Here are a few questions Why are there different alleles for a gene? Is the different alleles of a gene are mutated versions of a gene? Why selection pressure ...
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0answers
16 views

Why, evolutionarily, does the genus Latrodectus have such potent venom?

As far as I know, the venom of most species of spider in the family Theridiidae is not dangerous to humans. However, the genus Latrodectus is well known for having venom medically significant to ...
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1answer
49 views

Reversal form of endosymbiotic theory?

Cell's organelles give us evidence that they might have been independent organisms on their own. Are there any single-cell microorganisms known to have gone so to say this way back as well, i.e. ...
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3answers
74 views

Does evolution produce organisms perfectly adapted to their environment? [closed]

I have this biology assignment with this chosen topic. I have no idea where to start researching. I have studied the mechanisms and theories of evolution. I just don't know which relates to the topic. ...
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34 views

What advantage does a bird have from defecating in its drinking water?

We have a water table for birds. Only one bird uses it, a pigeon. This bird drinks from the water, then turns around and defecates into the water, then flies off. It returns later and does the same ...
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1answer
49 views

Is transition more common than transversion during the evolution of duplicated genes?

Transitions are base mutations of purine to purine (A <-> G) or pyrimidine to pyrimidine (C <-> T). Transversions are purine to pyrimidine or vice versa (A <-> C, A <-> T, G <-> C, G &...
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18 views

Possible to breed human-adverse mosquitoes?

Some time ago I read a paper on fruit flies, in which the researchers bred a population of flies to avoid a particular fruit. They did this by exposing the flies to two different types of food (say, ...
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0answers
24 views

Learning tensors for evolutionary or developmental biology

I'm looking for book recommendations on tensor algebra for use in biology. Tensors are being used increasingly in evolutionary biology and developmental biology, it seems. For example, here is an ...
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1answer
428 views

What kind of owl does this moth look like?

I found this moth and I noticed that it looked like an owl to me and remembered something about how some moths camouflages look like predictors? What kind of moth this is and what owl does this moth ...
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1answer
53 views

Examples of points in evolution where two species stopped being interfertile? [closed]

Apologies in advance for not using the right terminology here; I'm not a biologist. This isn't for homework or anything; just curiosity. I'm wondering: at what point do two divergent species stop ...
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0answers
18 views

How did craniates evolve?

Looking at most chordate phylogenetic trees, it seems that we usually have something like this: ...
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1answer
85 views

Population genetics indicates that a billion years are needed for establishment of the millions of genetic differences between human and chimpanzee

Genetic differences between human and chimpanzee include ~50,000 amino acid changes, ~30,000,000 point mutations in non-coding sequences, and millions of insertions, deletions, inversions, genomic ...
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1answer
81 views

Pangenesis and Lamarck's theory of inheritance of acquired characteristics

I've read that Darwin had split ways with Lamarck's evolutionary ideas. Yet his theory of pangenesis seems to support Lamarck's theory of inheritance of acquired characteristics. What am I missing?
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1answer
86 views

Are we evolving as fast as the oxygen is depleting?

How much oxygen saturation have we lost in the last 100 years? As oxygen levels dwindle and industry, deforestation, and population increases, at what year and saturation will the low levels of ...
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1answer
75 views

If wolves (or foxes) are fitter than rabbits, why rabbits have not become extinct? [duplicate]

I do not pretend to "demolish" the Darwinian theory of biological evolution and the "survival of the fittest", that's far from my intention. I have this doubt because of the fact that humanity, as ...
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1answer
36 views

What is the adaptive significance of temperature dependent sex determination?

Why do some reptiles have TDSD ? Is it because one of the genders is healthier than the other that only they, can survive high temperatures?