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Four quick flaws: 1) Environments are always changing. The fitness space is dynamic, and includes both biological and non-biological players, the former which are also ever-changing. Given a sufficiently stable ecosystem, one would expect an equilibrium among species to develop (though it could be cyclical). However even if the environment stays constant, ...


7

The flaw in his argument, from what I can see in your quotes, is to equate evolution to natural selection. Natural selection was never proposed to explain all evolution, nor how advantageous traits arise, but was proposed to explain how advantageous traits spread. Ultimately, why adaptation is so prevalent? The modern theory of evolution is so much more than ...


6

The topic you describe is very interesting and known as "species selection." Some traits exist that not only affect the reproductive success of individuals, but also affect the diversification rate of the entire species, either through affecting the extinction rate, the speciation rate, or both. To give you an example, I'll summarize this paper by Goldberg ...


6

I'll try to beat @Remi.b to the suggestion that you review Understanding Evolution as a general overview of evolutionary topics. For a quick answer: no. Sometimes people confuse the great importance of natural selection in evolution with an equivalency between natural selection and evolution. However, there are many many contributors to evolution, many of ...


5

TimeTree [http://www.timetree.org] is one site that allows you to look at times from divergence of various taxa. Their FAQ describes how they calculate the times by pointing to this paper: Tree of Life Reveals Clock-Like Speciation and Diversification, but in general they used standard molecular clock approaches. You ask about downloading their database: ...


4

Rephrasing the question Does evolution only give rise to traits that confer fitness? The phrasing is actually a little nonsensical, but it is easy to understand what you mean. The reason is that "fitness" is not a characteristic of individuals but a measure (a variable if you wish) of a characteristic. Imagine you are talking about Shaquille O'Neal and ...


3

$\ce{N2}$ may be abundant, but in the environmental conditions typical of Earth today, and back when life appeared, $\ce{N2}$ is nearly inert. That is, $\ce{N2}$ generally doesn't participate in chemical reactions except at higher temperatures or with special catalysts. $\ce{O2}$ on the other hand can participate in many chemical reactions at temperatures ...


3

While no perfect example exists, there are various different 'ring species' in nature where you have which species are able to interbreed with closely related populations, but there are least two "end" populations in the series. Examples include: Alauda arvensis, A. japonica and A. gulgula: Species of Skylark birds that coexist around Central Asia ...


3

Two obvious answers are genome doubling in plants, and Wolbachia-mediated infertility in insects. Both can cause one-generation speciation as measured by lack of interfertility. Polyploidy, which arises through complex genetic and ecological processes, is an important mode of plant speciation. This review provides an overview of recent advances in ...


3

This answer is towards the question, what forces primarily drive evolution such that we can observe a million species today? which is what the user wanted answered. To answer this question, we can start off at many places. So I wanted to start off at Kimura's neutral theory of evolution which encompasses both Natural selection and genetic drift. I wanted to ...


2

You are asking explanations about a creationist argument. One could provide explanations about some hypothesis that you may found in a science paper but not explanations for a creationist argument just because, by definition, a creationist argument is not supported by any evidence and logical thoughts. However, you may want to link to a creationist website ...


2

People who think in creationism or think about species rigidly might have a bit problem with that, so let me describe an example: When are humans "adult"? Legally, at 18 (or your national equivalent). However, everyone understand that people are becoming adult gradually. Sometimes, they "age" very quickly after some harsh experience (16 years old student ...


2

You take a population of fish and put them in a new environment (another planet even). Will they evolve? Yes they would evolve as long as they don't get extinct. It sounds very likely that they would very quickly get extinct though. Note, however that they were already constantly evolving while being on earth whether or not their environment was stable or ...


2

Micro- and macro- evolution are terms vaguely referencing to arbitrary time scales The terms microevolution and macroevolution have rather arbitrary and unclear meaning. For this reason, they are rarely used in the scientific literature. When they are being used, it is often in the first part of the introduction where general statements for which inaccuracy ...


2

The question is a bit confusing because it seems to be built on at least 5 misunderstandings. Allopatry and gene flow [..] allopatric speciation seen in the Galapagos finches. Adaptive radiation occurred because the finches flew from island to island, so there is gene flow [..] By definition, an allopatric speciation is a case of speciation where there ...


2

Insects and mammals diverged from one-another over 500 million years ago. For most of Earths 4.5 billion year history, life was single-celled, or organized into colonies of single-celled organisms. Likely sometime shortly before the Cambrian, multicellular animals evolved. The first multi-celled animals were likely a kind of colony that was not ...


1

Re a fly evolving into a rabbit, theoretically yes, practically no. Insects (and invertebrates in general) made some evolutionary "choices" like having an exoskeleton & breathing through trachea that put serious limits on their maximum size. (And vertebrates, particularly warm-blooded mammals & birds, likewise have limits on their minimum size.) ...


1

The two groups that you mention belong to two separated branches in the animal kingdom. The fly and all insects are protostomes and the rabbit and all mammals are deuterostomes. In the first, the embryonic opening (the blastopore) becomes the mouth, while in the second, it becomes the anus. Wiki At first glance, it seems like a simple difference. But it ...


1

Are biologists aware of the causation vs correlation problem or are they noobs in statistics? Evolutionary biologists tend to be pretty good statisticians. For historical consideration, Pearson is the father of the concept of correlation and was a biostatistician and Fisher is (one of) the father of evolutionary genetics and is also a famous statistician (...


1

Kostikova et al. 2016. Syst. Biol. developed an algorithm to model trait evolution with inter- and intraspecific variation. The authors use it to show whether a life-history trait (i.e. annual versus perennial) influences the evolution of intraspecific variation in the climatic niches of species While they do not directly incorporate the space component ...


1

Is there a difference? Yes, they are quite different things. What is group selection? Group selection is an view of evolution where selection acts at the level of the group, rather than the individual. It suggests that selection is mediated by fitness of the population, and leads to conclusions of things occurring for "the good of the species". It is ...


1

This example proves IMHO that migration is largely nature and not nurture: In the Netherlands, white storks were bred / reintroduced. A large part (about one third?) of the reintroduced birds do not migrate, but their offspring usually does migrate see. They couldn't have learned it from their parents, that's for sure.


1

Your math is wrong. Assume for simplicity that speciation is binary: that is, a speciation event divides one species into two. 50 million species is between 2^25 and 2^26. So producing that number of species in 3 billion years would require any lineage to speciate on the order of once per 120 million years. Remember, as per comments above, that evolution ...


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