10

Unfortunately it is not necessary to invoke group selection to answer this question. This is one of the reasons that Dawkins likes this discussion so much - he does not believe in group selection and so the discussion in SG does not invoke group selection. ESSs are described in the book as the product of direct competition or interaction between genes. ...


9

It basically comes down to a question of the unit of selection. From the common viewpoint, in which natural selection is seen as acting on individual organisms, it's almost a tautology that the organisms favored by selection are those that maximize their own reproductive fitness. Thus, the possibility that some organisms might engage in acts that help ...


7

In an infinite, well mixed population with single pairwise encounters, Grudger is indeed not an ESS. In fact, as you correctly note, in such a model the Grudger and Sucker strategies are indistiguishable, as the probability of anyone encountering the same individual twice is zero. To make it possible for the Grudger strategy to survive against invasion by ...


7

The field most closely associated with game theoretic models in biology is evolutionary game theory. If modeling is required, then the typical paradigm is agent-based modeling, and a good introductory book is: Yoav Shoham and Kevin Leyton-Brown [2009], "Multiagent systems: algorithmic, game-theoretic, and logical foundations", Cambridge University ...


6

The particular language a bioligist uses depends on the trade-offs between speed and ease of programming. Many models are written in C or Fortran if speed is paramount. On the other hand people will write models in higher level languages if speed is less important. These would be Python, R, MatLab, etc... In my models, which are written mostly in Python, ...


6

Your question is quite broad and asks for explanations for various behaviours which can lead to self-sacrifice. Religious reasons: The genetic influence here may be a predisposition to let others influence you. This is what gives rise to culture in the first place, in other words: the predisposition to at some point maybe sacrifice yourself because you are ...


6

There isn an effect called "Indirect reciprocity" where individuals just give to everyone they meet without direct requirement of reciprocity. This sort of benefit to others is common - hospitality to strangers, general politeness, good customer service all fall along these lines. You hope they will come back and benefit you again, but maybe they will ...


6

First of all, there is a very heated debate about this in the field of social evolution at present, and you aren't likely to get a conclusive answer. One theorist may give you one answer, but another will vehemently disagree. I'll start by logically answering your questions in reverse order! Question 2: Can you please provide an intuitive explanation of why ...


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

What you are describing usually falls under the category of computational biology or just mathematical biology. Unfortunately, the biggest part of this field is bioinformatics, or the application of statistical and/or dynamical programming techniques to sequence data. You exclude this in your question, and I would agree with you that it is a "boring" topic ...


5

It sounds like what you may be referring to is Fermi Paradox: The Fermi paradox — or Fermi's paradox — is the apparent contradiction between high estimates of the probability of the existence of extraterrestrial civilizations, such as in the Drake equation, and the lack of evidence for such civilizations. The basic points of the argument, made by ...


4

Joan Strassman's work is probably the route to go for this. The short of your answer is that several things mediate who ends up where in the slug: Cheaters are limited from exploiting other clones by high relatedness, kin discrimination, pleiotropy, noble resistance, and lottery-like role assignment. Here's the most relevant paper: Strassmann, J. E....


4

Nothing is at a genome-wide local equilibrium. Graham Bell wrote fairly extensively on this (IIRC). Some loci will be at what are likely global optimums (e.g. Cytochrome oxidase) will be at local but not global optimums (e.g. low-fitness malaria resistance vs. high fitness malaria resistance: for the extremely cool story check out this page) will not be ...


4

The $sR$ that your looking at is the average relatedness of the next generation. This assumes that the new immigrants into the the population are completely unrelated. So if the population is completely viscous ($s=1$) the average relatedness of the next generation equals that of the current generation. On the other hand, if the population is not viscous ($...


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 ...


4

The cat is probably just having fun. So, we could ask "What is the evolutionary benefit for having fun?" Through play, animal learn (Fagen 1974, Spinka et al. 2001, Pellegrini 2007, Hirsh-Pasek and Golinkoff, 2008). This is particularly true for juvenile. Adults play is not uncommon though and might follow from the same principles (Bekoff and Byers, 1998). ...


3

Tracing it backwards this was the earliest reference I found via google scholar, it's from 1988 and uses the $r B C$ notation in the format we are used to. Hamilton's rule states that for a social action to be favored under natural selection, rb - c > 0, where c is the cost to the actor in terms of the effect on (usually a reduction in) his expected ...


3

Have you looked into "Fundamental of Molecular Evolution" by Dan Graur & Li. Another suggestion in line of population genetics and different evo. theories would be - Evolutionary Genetics: Concepts and Case studies (Multi-author book. Editor Fox & Wolf)


3

Actually the derivation is pretty straightforward. It's easier to use the fact that $Cov(X,Y) = E(XY) - E(X)E(Y)$ to derive this result. Suppose $x_{j} = \sum_{i} s_{ij}$. \begin{align*} Cov (x_j, q_{j}) &= E (x_{j}q_{j}) - E (x_{j}) E (q_{j}) \\ &= \frac{1}{n}\sum x_{j} q_{j} - \frac{1}{n}\sum x_{j} q \\ ...


3

Are kin selection and group selection the same thing? Yes and no. Yes: These days people tend to use the "direct fitness approach" (Taylor and Frank JTB 1996). It turns out that this is based on EXACTLY the same equation as is contextual analysis, which is the currently favored approach for measuring multilevel selection in natural populations (...


3

The prototypical example of this is t, whose existence was predicted by Robert Trivers and featured prominently in the Selfish Gene. The current dominant point of view in evolutionary biology is that genes act in their own interest and even the 'self' is just a manifestation of the gene's reproductive properties. t is a locus in some male mice. The t ...


3

He defines lineage selection as selection for traits which increase the fitness of a group of plasmids, rather than an individual plasmid with in a cell or a particular cell containing plasmids. He says that the unit of selection are "plasmid-host clades" : in other words the unit of selection is the group of closely related plasmids in separate cells. It is ...


3

The writings by Samir Okasha (philosopher of biology/science) could be a good starting point. In his book Evolution and the Levels of Selection, he explicitly uses the Price equation to discuss selection at multiple levels (e.g. chapter 2.3: Price's equation in a hierarchical setting), and also derives a multi-level version of the Price equation: $$\bar{w}\...


3

It is just worded a little wierdly in my opinion. The key line in the paper is: 'Fitness components are also defined for all individuals, for example, $C$ is defined, even for a non-altruist, as the cost it would incur if were altruistic.' Essentially, if it doesn't matter what individual you are you always pay the same cost, then $C$ is a constant. This is ...


3

I don't know much about this particular species of snake but here are some info that may help. What do we mean by right-handed snakes? I doubt that in this context a snake could be ambidextrous. What they call handedness in these snakes (Pereatids) concerns the density and size of teeth on each side of the jaw (pictures from Hoso et al. (2010)) This ...


2

Selfish behaviour is not necessarily preferred. It depends on the game (game theory). For example, in absence of relatedness and reciprocity, we would expect: All the population defect in the Prisoner's dilemna Some defect and some cooperate in the snow-drift game Either all inds defect or all inds cooperate (depending on initial condition because it is an ...


2

I think the jury is out on this one, there are examples of evidence both for and against reachability of local equilibrium and even these examples can be interpreted in many ways. I present three pieces of evidence and some interpretations. In general, my feeling after reading about this is that the assumption of equilibrium is ingrained in mathematical ...


2

What I think the question is "Why wouldn't an organism be more efficient from selection than the environment demands?" Please let me know if I'm hitting the mark here. A scenario suggested by the question is this: If there is selection pressure on say an animal to resist a disease, and then it evolves two resistance systems to the disease. This could be ...


2

Is it interesting? Perhaps, but "complexity" is a vague notion. If you want to simplify and just say "variation" then sure, sex increases variation. But so does that random mutation you brought in. Really, all you need for increased variability is some difference between generations and genetic Drift will take care of the rest. Mutation is enough, which ...


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