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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7answers
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How do we know that humans and chimpanzees evolved from a common ape ancestor? [closed]

Richard Dawkins in one of his videos says that Evolution is a fact and not just a theory. He goes on to say that man and chimpanzees both evolve from apes. Is this correct (Is evolution a fact and ...
3
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1answer
248 views

Do mammals and birds have a common warm-blooded ancestor?

Is it homogeneous or did they converge? Did we both evolve from warm-blooded reptiles that are extinct maybe?
2
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0answers
53 views

Front versus back in animal anatomy [closed]

Throughout various species, there seems to be a clear distinction between the front and the back. The musculature of the front, when engaged, closes or curls up the body, protecting it, while the ...
0
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2answers
66 views

When did the most recent common ancestor of all living domestic dogs live?

Wikipedia provides a very detailed page on the origins of the domestic dog, but this fact does not seem to be present there. Google searches for terms such as "most recent common ancestor (MRCA) of ...
0
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1answer
213 views

How does the modern synthesis theory explain the evolution of birds from dinosaurs? [closed]

The theory of evolution claims that birds evolved from dinosaurs only by mutation, genetic drift, migration and natural selection. However, it seems to me that wings were not selectively advantageous ...
7
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4answers
334 views

How does Darwinian Evolution work?

Let me explain... A friend and I read some articles, part of a Biology book, and watched a video on evolution. We then tried to explain what Evolution is to each other. My friend said that Natural ...
2
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1answer
77 views

Discrete vs Continuous Replicator Dynamics

The replicator eqn in the case of discrete non-overlapping generations and asexual reproduction is given by the discrete replicator eqn: $$x_i(t+1) = x_i (t)\frac{f_i(t)}{\bar f (t)}$$ where $x_i$ is ...
5
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1answer
1k views

If oxygen is such a good energy source, why do plants release it?

Why do plants release excess oxygen, rather than consuming it entirely given it is an excellent energy source?
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2answers
516 views

Why do snakes not have eyelids?

Why is it that snakes do not have eyelids? Is it due to that fact that they are not as evolved as we humans and other organisms that have eye lids, or is there any other significance behind it if any?...
5
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2answers
90 views

Evolution of spider webs?

Web making seems like a fairly complex behavior built from a pretty strong material. So how exactly did it evolve? Do we have any clues about what kind of features/behaviors preceded web making and ...
0
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1answer
56 views

What, if anything, would prevent flying fishes evolving to be capable of extended flight? [closed]

This extraordinary video documents a flying fish gliding above the surface of the sea for nearly two minutes. Occasionally it uses its tail for added impetus. It is possible to imagine a fish gliding ...
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1answer
96 views

Is there an evolutionary advantage for coconut oils to be rich in saturated fats?

I know that coconut oil is composed of multiple saturated fatty acids, but is there a reason why this would have increased the fitness of the coconut plant?
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1answer
87 views

How to statistically test the predictability of evolution? [closed]

Can anyone recommend me an experimental study which tries to test the predictability of evolution? The closest works I found are the studies of fluctuation tests (f.e. classical study of Luria & ...
14
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2answers
298 views

Are some animals, like dogs and cats, color-blind and how do we know that?

I have heard that some animals, including dogs, cats and donkeys, are color-blind. They cannot recognize any color. Is that true? And how can humans verify that animals are color-blind, or not? During ...
0
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0answers
67 views

How can the number of chromosome change during evolution

I found an explanation here, which is basically saying that sometimes the centromeres are duplicated, breaking a chromosome into two halves. But how could this propagate? I don't think inbreeding is ...
4
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1answer
70 views

Which Darwin book (and today edition) is illustrated by his own drawings?

I am interested in buying Charles Darwin books and mostly drawings (nowadays editions, I am not a collector). Please, can you advise in which book and which edition I can find the most of his drawings?...
2
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1answer
52 views

What contributes to the variation of protein sequence across different species?

What contribute to the variation of protein sequence across different species (e.g. phenotype, environment, evolutionary pressure) and how do those factors contribute to the variation? I have tried ...
0
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0answers
31 views

Are there any biological obstacles prohibiting lighter-than-air organisms? [duplicate]

Why there are no organisms that use cavities filled with lighter-than air substances (e.g. hydrogen) to fly and remain in air? Given that there are a lot of fish and algae that use similar cavities ...
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2answers
82 views

Is this a simple Hardy-Weinberg problem?

Phenylketonuria is a severe developmental disability due to a rare autosomal recessive allele. Approximately 1 in every 10,000 newborns suffer from this disease. Calculate the frequency of the allele ...
0
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1answer
67 views

Have there been any macro-evolution experiements?

I'd like to start first by saying that I don't believe in creationism at all, nor any non-Darwinian-evolution explanation of the diversity of life on Earth. The theory, the fossil record, and the ...
5
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2answers
73 views

Do dingos 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 ...
35
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3answers
4k views

How could humans have interbred with Neanderthals if we're a different species?

To be clear, I'm not doubting that homo sapiens and homo neanderthalensis did interbreed: of that much I'm convinced. Within the past few years I've seen an upcropping of pop-sci articles discussing ...
3
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2answers
101 views

Why we have to damage our muscles to build them?

I know that new muscle cells are made when actin fibers are disrupted. My hypothesis is that muscle mass is limited, from birth, and that nutrients (protein) are only directed to grow muscle when ...
0
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1answer
38 views

Genome Sequencing [closed]

Is Genome sequencing used to determine the relationship between two species that are believed to have a common line of descent? How accurate is this method if so? Are there more accurate methods ...
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0answers
185 views

Why are hybrid offspring mostly sterile? [closed]

Hybrid infertility is a common trait in cross-species offspring. Most are sterile, as they do not produce viable gametes. Examples of this can include Ligers and Mules. Could modern advancement in ...
0
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0answers
23 views

Relationship between selection coefficient and frequency of elimination

I'm asking this question because I would like to model the influence of changes that take place during tumour evolution to estimate what changes are selected against. I am in effect looking at ...
1
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1answer
93 views

Bootstrap question

I have a question about bootstrapping: The way that I understand it is that each number represents how well a given node is supported. So in the diagram presented, we can see that the "Seal-Bear-Cat" ...
0
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1answer
272 views

Why don't we have two hearts? [duplicate]

The human body is amazing. But there seems to be some evolutionary changes that appear to not make sense regarding redundancy. While not necessarily the primary reason for their existence, the human ...
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0answers
12 views

What explains the different nutrients of seeds?

I was eating a orange while at work and thought to myself, "Why are oranges sugary, and avocados fatty?" They functionally both do the same thing, right? So my thoughts are simply that this is ...
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1answer
78 views

Why isn't the biological niche occupied by whales instead occupied by fishes?

As by the title. Why aren't there many more, and larger, whale shark like creatures instead of the great mammalian swimmers? I'd assume fish have a benefit in doing the whole "being under water" thing ...
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0answers
15 views

Rates of evolution of mitochondrial genes

I am interested in knowing the rates of evolution of different mitochondrial genes (in base pairs per million years) across different taxa. Has there been any publications along these lines ?
0
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1answer
154 views

Why do we breath oxygen? [closed]

I like this contradiction. But seems like my Biology teacher doesn't. If oxygen oxidates us, why do we breath it? Why can't we evolve into a new kind of human being that breaths other component of ...
8
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2answers
370 views

Why do squirrels have twitchy bushy tails?

Whenever I see a squirrel in the woods, it is always the big bushy tail flipping around that gets my attention first. A pray animal with a big bushy flag calling attention to it's self seems to be ...
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2answers
80 views

What causes goose bumps?

What is the actual process and reflexes that cause the goose bumps? Why is it an evolutionary advantage to have goose bumps in the first place?
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1answer
107 views

Question on Evolution [closed]

Scientists say there are 15 million insect species, 2 million marine species, more millions of bird and animal species. Yet, only one- humans - developed language. If evolution is true - that species ...
3
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1answer
165 views

Are there examples of animals that adapt to their environment very quickly? The phenomenon is called Phenoptic Plasticity [closed]

Evolution and speciation may take millions of years. This made me wonder if there is an animal that adapts itself relatively rapidly to its environment? I don't mean a simple adaptation like a change ...
5
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2answers
1k views

Why do adult insects have 6 legs?

Apparently, there is an advantage to having 6 legs in the insect world. What is that advantage, if anything? Why would such an advantage exist for insects, but not for other, larger land animals? ...
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3answers
210 views

Did we evolve from monkeys?

Since I was young, I always understood that evolution taught that we descended from monkeys (or apes, not too sure a distinction was ever made). However, someone recently told me that this isn't ...
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2answers
210 views

How quantitative is the theory of evolution right now? [closed]

We developed complex structures like eyes and brain, whose mechanisms rely on specific species of molecules and relevant chemical reactions. But we did not develop an enhanced night vision, the ...
6
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1answer
638 views

Evolution home experiment?

If I were to take bakers yeast and put it in medium of minimal sugar(whatever quantity that would be) and rice(for a source of starch), could the yeast have a "evolutionary leap" and adapt to use the ...
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0answers
70 views

Why did life on Earth develop with two sexes? [duplicate]

If evolution gives us the best adapted organisms for survival of the fittest, why does so many of Earth's organisms require two sexes for reproduction? Shouldn't this have been bred out of our ...
11
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4answers
691 views

How did the first life form on Earth reproduce without DNA?

How did the earliest life forms exist without DNA? The most likely scenario I can think of for life happening from nothing is that, over billions of years, with trillions of water molecules and dust ...
0
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1answer
45 views

Biological Evolution outside of Earth [closed]

What drives evolution forward? I heard that climate change drives species to evolve and adapt. Is there any other mechanism that is encoded in our DNA by which species can over abrupt changes, evolve ...
2
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1answer
51 views

Who was the first to coin the terms of soft and hard selection?

Soft and hard selection are sometimes used with different definitions. I have been told that at first place hard and soft selection has been defined in the following way: soft selection: Each deme ...
2
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1answer
134 views

Is the fixation rate always equal to the mutation rate for neutral alleles?

Background A classical result of population genetic is that the rate of fixation of netreual alleles is the mutation rate $\mu$. The reason is that each generation $PN_e\mu$ mutations enter the ...
4
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2answers
264 views

Why are there so many different humans yet chimpanzees are just chimpanzees?

There are two species belonging to the Pan genus (Pan troglodytes and Pan paniscus). That's just two. I mean, humans have changed radically since we split from chimpanzees, we have Australopithecus ...
5
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1answer
154 views

The replicator equation vs the Lotka-Volterra equation

Background The replicator equation with $n$ strategies is given by the differential equation: \begin{equation} \dot x_{i} = x_{i} \left( \sum_{j=1}^{n} a_{ij}x_{j} - \phi \right) \qquad i = 1, \...
1
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1answer
391 views

What is a selective constraint?

I encountered the term selective constraint in Huber et al. 2015, page 4 (last paragraph) in: If invariable sites are included in the analysis, then both the methods of Kim and Stephan (...
21
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1answer
573 views

Why are many fruits sour?

Many fruits (like apples, berries, citrus fruits etc.) contain high levels of organic acids, especially malic acid and citric acid. Are there any evolutionary functions of those acids in ripe fruits? ...
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0answers
65 views

What are constrained genetic elements?

I am somewhat of a newbie in evolutionary biology currently taking my first steps in bioinformatics. I was reading a paper when I came across the term "constrained genetic elements", referring to ...