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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275 views

Can you answer Ray Comfort's question on Biological Evolution? [closed]

https://www.youtube.com/watch?v=U0u3-2CGOMQ There's this video on Youtube about biological Evolution that has gone viral. I'll paste it above for your convenience. To cut to the chase, Ray Comfort ...
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1answer
74 views

Can nature create codes and specified complexity? [closed]

Is there an example of nature creating codes or specified complexity? It is said by Creationists that codes can only come from minds, and since DNA has a code, it was created by a mind. Is this true? ...
3
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1answer
65 views

What's the use of RNA editing in kinetoplast?

The genes of the mitochondrion (kinetoplast) of some Kinetoplastida - e.g. Trypanosoma brucei, the parasite which causes African sleeping sickness - are "encoded" in a way that the pre mRNA requiries ...
8
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2answers
2k views

why is AUG the initiation codon?

Is there any reason why AUG is the initiation codon ? Why is there a need for an initiation codon ? Can't translation start with different codons?
3
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2answers
170 views

Why and how does complexity usually tends to increase through time?

The question of complexity is classic in the very first lectures of evolutionary biology where the teacher usually tries to tell the students that complexity does not necessary increases and that ...
7
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2answers
148 views

The Assumption of Weak Selection?

I was reading this question and I failed to fully understand the introductory part of it. The OP (@Artem Kaznatcheev) says: Most analytic models like to assume weak selection because it allows ...
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2answers
79 views

Could a normative population ever be non-heterosexual? [closed]

In the modern documentary called "Bi the way", one American geneticist said that if modern American youngsters may as well be functionally bisexual, then some generations ahead Americans could be ...
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1answer
1k views

What are the differences between G+ and G- bacteria?

The distinction between Gram-positive and Gram-negative bacteria is based upon the Gram staining method, that reflects the bacterial wall physical properties. However, this classification involves ...
2
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1answer
49 views

Evolutionary conservativeness

List the following proteins in the order of decreasing evolutionary conservativeness of their primary structure: Somatotropin. Catalytic subunit of a DNA – polymerase. Histone H1. ...
5
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2answers
819 views

Why do we assume that the first humans were dark-skinned?

According to the article Dark skin and blue eyes: How Europeans once looked: It is widely accepted that Man's oldest common forefather was dark skinned, and that people became more pale as they ...
0
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0answers
40 views

What percentage of possible proteins has been tested by human brain evolution?

When the human human brain is discussed, I frequently hear an argument that goes like this "If there was a simple chemical solution for people to be smarter, nature would've already found it". I'm ...
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2answers
287 views

How did fish evolve the ability to breathe on land?

Doesn't make sense. It would be like a human evolving the ability to breathe on the moon without a spacesuit. How would the organism be able to carry out such an evolutionary adaptation, when the ...
7
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3answers
157 views

How should I put a large phylogeny into a scientific paper?

I've been trying to put a phylogeny tree into a scientific paper. This tree includes ~220 species, which is too too large for one page for journal articles (Letter or A4 size). But in my paper it is ...
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1answer
571 views

Evolution- Variations, adaptations and selective advantages

I am trying to understand Variations, adaptations and selective advantages and how they are all related. Feel free to add or correct me if I'm wrong- Variations are structural, functional, or ...
1
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1answer
101 views

Can we say that microevolution and macroevolution is fundamentally the same thing over different time scales?

This Wikipedia article states: Macroevolution is evolution on a scale of separated gene pools. Macroevolutionary studies focus on change that occurs at or above the level of species, in contrast ...
4
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1answer
237 views

Why do farts stink, but perfume does not?

Why is it that natural things like farts, poop, halitosis etc., from which we are always surrounded smell "bad"; whereas manufactured products, such as perfume or glue smell "good" to most of us? In ...
3
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1answer
216 views

Macroevolution vs. microevolution

Where is the line usually drawn between macroevolution and microevolution? I thought that, although similar processes govern both, the line was at the species level, with macroevolution being changes ...
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4answers
276 views

Are we inevitable in the evolution?

Suppose we wind time back to the instance when life emerged on Earth and let evolution start over again, will human beings or any other kind of self-conscious animals evolve ultimately, inevitably? ...
10
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1answer
299 views

The Origin of Mitochondria

For a long time I've just accepted, because it is just what everyone told me, that mitochondria became organelles in the cell when they were "engulfed" by another cell which acted like it's host. This ...
21
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4answers
666 views

How many times did endosymbiosis occur?

According to the endosymbiont theory, mitochondria and chloroplasts originated as bacteria which were engulfed by larger cells. How many times is it estimated that this occurred in the past? Are there ...
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1answer
103 views

Definition of “Regime of selection”

How would you define Regime of selection (or Selection regime)? In addition to a accurate definition, a developped example ...
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2answers
137 views

Evolutionary history: did any organs start out as autonomous organisms?

I've read that the cell nucleus was once an autonomous organism that was "enslaved" by the larger cell at the time of the Eukaryotic Revolution. Are there any organs in the human body that we know of ...
2
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2answers
156 views

Book recommendations for algorithms used in evolutionary biology

Do you have recommendations for a book that presents the different algorithm used in theoretical evolutionary biology? I don't mean evolutionary or genetic algorithms (otherwise this question would ...
3
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1answer
413 views

Ka/Ks (dN/dS) analysis module for Python?

From this wiki article: In genetics, the Ka/Ks ratio (or ω, dN/dS), is the ratio of the number of Nonsynonymous substitutions per non-synonymous site (Ka) to the number of synonymous ...
4
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1answer
179 views

Birds from the Family Columbidae Feed Young “Crop Milk”

Birds from the family Columbidae (e.g., doves and pigeons) produce a fatty, milk-like substance in their crop. The secretion is often referred to as "crop milk." They feed crop milk to their young ...
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2answers
118 views

Is there theory that connects longevity, time-scale of environmental disturbance, and adaptation?

I'm thinking here about environmental disturbance or like climate change-driven warming. It seems as if there are two macroevolutionary ways to deal with environmental change: 1) Have short ...
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1answer
168 views

I believe in variation of a species but not in evolution [closed]

I can see that variation within species exists, for example birds with various size beaks adapted for specific food-gathering purposes, one may have a larger beak vs. smaller beak, OK that works for ...
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1answer
118 views

Does conjugation support gene selection?

I have already posted this on chat but haven't got any response. A recent question on group selection stimulated me to ask this here. QUESTIONS: Why should bacteria conjugate? If we consider that a ...
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1answer
208 views

DIfference between diversification and differentiation

In Adaptive dynamic : what is the difference between Ecological Differentiation and Ecological Divergence ?
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1answer
92 views

Current human behavior as a genetic heritage

People: I have doubts about genetic heritage, but let me explain the context which has shown up this doubt for you: I was debating about sexism and the following question were put on the discussion: ...
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2answers
330 views

What are the evolutionary niches differentiating an apple from a pear?

So, as far as I understand (basic) evolutionary theories, diversity is generated by "niching." That is, if there is an environmental factor that hasn't been fully used by any species to "profit" off, ...
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2answers
116 views

How likely is it that Earth has millions of different species?

I know that the probability of life existing on a habitable planet is pretty slim. But, how likely is it that it hapenned millions of times in the same planet? Or was it only a few species that ...
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4answers
285 views

How come most animals never seem to evolve over millenia?

People often say, including those with extensive knowledge in biology, that a certain species of animal will evolve in one way or another: 1.From changing environments. 2.Mutations. 3.Possibly even ...
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2answers
158 views

Is there any genetic similarity that defy evolution theory?

For example, say species A is common ancestor of B, and C. Species B is a common ancestor of D and E. We would expect that there will be more genetic similarity between D and E than D and C. And ...
2
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1answer
156 views

What are the visual, behavioral similarities and differences between Yellow Fever Mosquito (Aedes aegypti) and the Tiger Mosquito (Aedes albopictus)?

The Tiger and Yellow Fever Mosquito visually look very similar. Recognizing the difference is important for tracking and controlling the spread of Yellow Fever, Dengue fever and other diseases. ...
2
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2answers
517 views

Are there genetic similarity between humans and pigs that don't exist in chimps?

Chimps are our closer relative. Any genetic similarity between humans and chimps must exist on the common ancestor. Pig branch out sooner. So, any genetic similarity between humans and pigs must be ...
5
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1answer
43 views

Is there any evidence telling us what the oxidation state of early earth's atmosphere was?

I ask this question in relation to the origin of life. I realise it would probably be better suited to a geology stack exchange, but it does not yet exist. The Miller-Urey experiment gives a lab ...
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1answer
92 views

Does avocado and orange have a common ancestor?

While I'm eating my orange, I felt as if I was eating avocado. It might be genetic manipulations perhaps but it made me think if they have a common evolutionary ancestor. Is there?
3
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2answers
722 views

The number of nipples (breasts) a species has?

Only mammals have mammaries and mammary glands. What evolutionary factors determines the number of mammaries (nipples/teats/breasts) a species has? Is it always an even number?
3
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1answer
71 views

Chemoautotrophy in large organisms?

The major nutritional mechanisms include chemoautotrophy, heterotrophy (including parasitism and saprotrophy) and photoautotrophy. All of these modes of nutrition developed first in prokaryotic ...
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1answer
337 views

Cats, Dogs and Bears - how are they related?

What is the ancestral relationship between cats, dogs and bears? I presume they are more closely related to one another than other paraphyletic clades of mammal. Which came first? What did their ...
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2answers
154 views

Effect of zero selection (pressure) on the population health

Evolution naturally produces better features: stronger muscles, teeth and minds. Killing the weakest, evolution wipes defective genes out of populations. The mutations are necessary for advance. ...
4
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1answer
106 views

Natural enemies boost deep evolutionary fitness?

"Two species that reduce one another's fitness on microevolutionary (short-term) timescales can increase each other's macroevolutionary (long-term) fitness" Opinions? Intuitive Examples: ...
3
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1answer
51 views

Are there cannibalistic k-selectors?

My understanding of r- and k-selectors does not go deeper than the wikipedia article. I understand k-selectors to be creatures that put tendentially more effort and energy into rearing their ...
8
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1answer
137 views

Is there a comprehensive database of fossils (with images) online?

Not sure if this is the best stackexchange to ask... I have not been able to find a decent database of fossils on the web, does one exist? Here are some of the links I have found through Wikipedia ...
4
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1answer
58 views

How much can you learn about species variation from a skeleton?

I just read about the discovery of the 1.8-million-year-old human skull in Georgia, and how it suggests that early humans were all one species instead of distinct ones. Would an archaeologist ...
15
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5answers
720 views

How is evolution possible in contemporary humans?

I would like to know if evolution is continuing to happen in modern humans, assuming things like existence of the nuclear family structure, fidelity to one partner, etc. It seems to me the answer ...
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1answer
160 views

What is the most recent non-primate ancestors of humans?

If we go down the evolutionary tree of humans, (Homo sapiens, Homo erectus, ...), what will be the first non-primate ancestors?
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3answers
1k views

Does Darwin's Theory of Evolution refute Terence McKenna theory “Stoned Ape” theory of human evolution?

I haven't read it but I'm asking for a quick answer. As far as I know, Terence McKenna's theory of evolution in humans main concept is that a hominid has tried in their diet psilocybin mushrooms, and ...
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1answer
60 views

Does the existence of one species imply the existence of many other?

Reading one of Sir Arthur Clarke's scifi stories, I came across a statement something to the effect of, existence of a single species automatically implies the existence of many other species. So ...