Questions tagged [evolution]

Changes in the heritable attributes of populations of organisms over time. The mechanisms of evolution are mutation, migration, drift, and selection.

Filter by
Sorted by
Tagged with
0 votes
1 answer
59 views

In this representation of the tree of life, what are the lateral connections?

I found this simple representation of the tree of life in a wikipedia article, and I was curious what these horizontal connections shown here are supposed to be, like the ones between plants and ...
0 votes
0 answers
21 views

Where is the position of PV92 locus?

The PV92 locus may contain an ALU- SINE that is used for phylogenetic reconstruction. The literature mentions that PV92 is located at chr16 and is part of an intron. However I can’t find anything on ...
2 votes
2 answers
93 views

What motivates an organism to reproduce?

What is the biological factor (gene or something else in case of humans) which motivates an organism to reproduce? By reproducing the evolutionary success of an organism increases. But why would an ...
1 vote
1 answer
38 views

How to judge the distance of nodes in biological evolution tree

I would like to know the method of judging the distance between two nodes in the phylogenetic tree. For example, in the diagram below, is node 299 closer to node 151, or closer to node 201?
0 votes
0 answers
31 views

How do we know how long speciation occured?

Just as we use radiometric dating to age rocks, what is the method used to age how long ago speciation occurred in genetics?
1 vote
0 answers
64 views

Is there non-coding DNA common to all living things? [closed]

I saw the question asked about proteins common to all life, and was happy to see there are proteins common to all living things. Similarly, I wonder if there are portions of non-coding DNA that are ...
7 votes
3 answers
8k views

Why do some animals have 8 Limbs (e.g. Spiders, Octopuses)?

Octopuses have 8 tentacles, spiders have 8 legs. Is there something special about 8? It seems like an animal that needs 360° mobility has 8 legs.
2 votes
1 answer
74 views

Are there internal systems of organisms which acquired the functions which they were not evolved to perform?

In his research on the issue of belief formation Daniel Gilbert (1991. How Mental Systems Believe) claimed that cognition "is an evolutionary outgrowth of [perception]." What he meant is ...
1 vote
5 answers
149 views

Is it true that every organ was inherited from common ancestor?

For me it seems nearly impossible that two different branches of evolution came up to same organ or feature. Is there any proof or refutation that every organ or feature was inherited from common ...
1 vote
0 answers
62 views

Why Sexual Reproduction instead of Gene Transfer?

So, as I understand it, the prominent theories for the evolution of sex are that it increased variation allowing for faster adaptation in evolutionary arms races, and that it gets rid of deleterious ...
0 votes
0 answers
30 views

How does the cell-wall ultrastructure of gram negative bacteria justify it being unable to Sporulate?

The following is a quote from my Microbiology Lecture PPT: "Some gram positive bacteria but NEVER gram negative ones produce spores under harsh conditions". It got me wondering why gram ...
3 votes
2 answers
1k views

Why don't the female lions in a pride help their male lion to protect their children from other males?

I watched a dozen of videos taping the fights between male lions; none of them involve female lions assisting in the fight. It is also known that the male lion who take-over the pride will kill all ...
2 votes
0 answers
44 views

Does the X/Y sperm ratio in male ejaculates depend on circumstances of sex and who they are mating with?

Male mice are known to have different X/Y sperm ratios in their testis. Possibly, this phenomemon is not limited to the mice. However, can the males utilise that to their advantage? For example, ...
2 votes
2 answers
78 views

How does evolution work at the level of a caterpillar mimicking a snake?

I am referencing this video, where a caterpillar turns into what looks like a snake when it gets frightened, presumably to ward off predators. Now how can this evolve? I majored in Molecular ...
2 votes
2 answers
5k views

Why do humans seem to be the only mammals that like spicy food?

Peppers evolved chemicals like capsaicin to discourage animals from eating them, and that chemical itself can cause internal damage if consumed in large quantities, though this is usually only a ...
2 votes
0 answers
65 views

How does embryology provide evidence for evolution?

I am not a biology student, I just have a profound fascination and appreciation for biology, and from time to time I like to read and watch videos about it. I was reading about evolution when I came ...
2 votes
0 answers
75 views

Has network theory been successfully applied to protein expression within a cell?

I saw the following passage in the NPR 13.7 Cosmos & Culture commentary post The Big Idea Behind Big Data. Using the Internet's first generation of Big Data, researchers like physicist Albert-...
0 votes
1 answer
61 views

Reasons for the existence of symporters and antiporters

I'm wondering what is an evolutionary adaptation to the evolution of symporters and antiporters instead of just uniporters. Antiporters might help preserve electrical neutrality by pumping in/out an ...
7 votes
2 answers
368 views

Can diploidy evolve in absence of sexual reproduction?

Theoretical question Can diploidy (or polyploidy) evolve from a haploid lineage in the absence of sexual reproduction ? For what theoretical reason? How can such evolution take place? Empirical ...
2 votes
1 answer
1k views

What is the advantage of the inverted image on the retina?

Recently, I learned that the image of the world which we see actually reaches the retina inverted. This is due to the fact that the retina lies behind the focus of our eyes. I have two questions: ...
0 votes
0 answers
53 views

How quickly could mice evolve to avoid mousetraps through artificial selection?

So, we have a mouse problem in our attic. I set traps routinely to keep the population down. We have taken pains to exclude them by sealing cracks and holes, etc., but they still manage to find ...
0 votes
0 answers
71 views

Mechanism of Modern Human Evolution

The known mechanisms behind Classical Evolution are natural selection and gene mutations. The process through which lifeforms evolve is basically trial and error. Many individuals are created with ...
4 votes
4 answers
1k 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 ...
5 votes
1 answer
128 views

How have some cancers "evolved" to be so aggressive and treatment-resistant?

[In this post, I may ascribe agency to processes, inanimate objects or microorganisms: this is rhetorical, I know they don't "intend" anything. I will also use "evolution" in a ...
109 votes
9 answers
22k 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 ...
6 votes
5 answers
2k views

Is natural selection a tautology, and therefore not truly falsifiable?

I've heard the argument from a lot of creationists that all the evidence for natural selection (and by extension, evolution) in general is worthless because natural selection is so flexible that it ...
1 vote
0 answers
56 views

Confused About Why Red Queen Hypothesis Wouldn't Apply to Deer's Color Vision [duplicate]

In this site,https://www.livescience.com/why-are-tigers-orange, it says ""But there seems to be no evolutionary pressure, particularly for deer, which are the main prey of the tiger, to ...
4 votes
1 answer
108 views

Is there any evolutionary reason why male traits appear in the heterogametic sex and female traits in the homogametic sex?

If you define male as the heterogametic sex, and female as the homogametic sex, then my question sounds like a tautology. But, what I'm trying to get at is why is it that the traits we associate with &...
0 votes
2 answers
83 views

What is meant by "Common descent"?

"Common descent is a concept in evolutionary biology applicable when one species is the ancestor of two or more species later in time." (Wikipedia) [Credit:https://bio.libretexts.org/...
-1 votes
1 answer
138 views

Are babies cute, or is cute babies?

I have no doubt that the cuteness of babies is an evolutionary advantage. So the 'why' is clear, a bit of research also explains the mechanics, such as babies having certain features that trigger ...
5 votes
1 answer
1k views

Ways to distinguish between purifying selection and selective sweep

When looking a population genomic data, regions of low diversity (lower than expected; such as in a region of high recombination) can indicate either purifying selection of deleterious mutations or a ...
8 votes
0 answers
94 views

Why are animal's whiskers in a square lattice?

I was observing my cat up close when I noticed his whiskers were in a square lattice as a novice mathematician, took notice of it and wanted to know if any other animal had this peculiar feature, so I ...
4 votes
1 answer
83 views

Century old trees and evolution

We always think of natural selection as occurring at the level of populations not individuals. how about century old trees where germline is being produced from constantly dividing cells. Are all ...
0 votes
0 answers
17 views

Why do rock monitors have such large snouts?

I'm looking into the anatomy of different types of African monitors. I came across the rock monitor, one of the largest lizards in Africa. One of the defining characteristics of this species is it's ...
0 votes
1 answer
70 views

Could life protect itself from ultraviolet radiation? [closed]

I have heard it argued that life as we know it (DNA-, RNA- and protein-based) could not have evolved without the ozone layer to protect it from UV radiations. It seems to me that mechanisms to deal ...
1 vote
2 answers
236 views

Darwinism and the idea of being too successful

Is there an example of any animals or insects that have evolved too efficiently and went extinct due to upsetting the homeostasis of their environment? Outside humans. I was thinking about venomous ...
-2 votes
1 answer
115 views

Given that "genetic drift" can happen, why is searching for an adaptive explanation for traits considered an important scientific question?

I saw today on Wikenigma (a wiki for open questions in science) that there are many competing explanations for why zebra stripes are evolutionarily adaptive, and there is no consensus on which one(s) ...
7 votes
3 answers
1k 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 ...
3 votes
1 answer
2k views

What are Some Classical Examples of Local Adaptation?

Question Can you please give a list of classical (textbook) examples of local adaptations? How to answer Examples don't necessarily need to include what evidence supports this specific example of ...
2 votes
0 answers
81 views

Have lions, tigers, and cheetahs begun to lose or not yet fully gained tree climbing traits?

Leopards, jaguars, and the domestic cat all regularly climb trees, but lions and tigers rarely do. From what I can tell from a basic online search, the latter are inexpert tree climbers, but they ...
0 votes
0 answers
64 views

What is the evolutionary purpose of citric acid?

According to Dr. Paul Saladin, fruits are brightly coloured and sweet because they want to be eaten to spread the seeds of the plant. Unlike roots stems seeds and leaves that don't. To deter ...
2 votes
1 answer
263 views

What is "Correlation of growth" according to Darwin and was he correct about it according to modern science?

What are the views that modern biologist have on Correlation of growth? I need some clarification on statement that I'm gonna mention below as well that is it reason to that as mentioned here: "...
3 votes
0 answers
244 views

Do dingoes show wolf 'characteristics'?

I've read that Russians have been performing selective breeding on Red Foxes for about fifty years, aiming to make them tame. The wikipedia article says The experiment was initiated by scientists who ...
32 votes
4 answers
5k views

Were there any flying dinosaurs?

I've seen some articles which came in contradiction with each other. The first article was talking about flying dinosaurs, dinosaurs with feathers and so on. A couple of other articles are talking ...
0 votes
0 answers
39 views

What came first: the ribosome in which RNA is read, or the RNA to encode for the ribosome proteins? [duplicate]

It's a bit like the chicken-and-egg problem. Ribosomes need proteins because they are partially made of them. Where can they get their proteins? They read the base sequence in mRNA entering them, ...
1 vote
0 answers
71 views

DNA from Egyptian Mummies Evolution vs Human of Today

Comment: I ask my biological questions from the point of view of mathematical proportions. I am not a biologist. Are there significant differences in DNA from Egyptian Mummies vs. those available from ...
0 votes
0 answers
11 views

Why are precultures done in Luria-Delbruck fluctuation assays?

I looked at a variety of descriptions of the classic Luria-Delbruck fluctuation assay protocol for determining mutation rates in different organisms (e.g. 1, 2, 3) and noticed that they all start from ...
0 votes
0 answers
42 views

Would the environmental pressures imposed by humans make the housefly of today significantly harder to swat than their ancestors of 1000 years ago?

For context, I am primarily referring to Musca domestica. Recently the thought occurred to me that due to short life cycle of the common housefly, and due to the fact that such flies have interacted ...
2 votes
0 answers
15 views

How to get an adaptive landscape from a fitness function?

In Schluter (2000), it is mentioned that one can convert a fitness function (see image (a)) to an adaptive landscape (see (b) and (c)). The key is to calculate the mean phenotype of a population and ...
8 votes
2 answers
939 views

Is abiogenesis possible today?

Life on earth started about 3.5 billion years ago. I would assume abiogenesis happened because the conditions were right. Would the current earth conditions allow for new abiogenesis and completely ...

1
2 3 4 5
44