Podcast #128: We chat with Kent C Dodds about why he loves React and discuss what life was like in the dark days before Git. Listen now.
10

The whole point about your question is to define what is an "evolved trait"? The concept of "evolved trait" does not exist in evolutionary biology. Here are various definitions I can think of that could apply to the expression "evolved traits". Heritable Traits Does evolved traits mean heritable traits? A trait may be heritable or not. See for example my ...


7

It is useful to think in terms of the proportion of genetic material that an individual gets from each parent and the amount of this genetic material that will be shared with another individual (on average), and then sum this together i.e. as: $ relatedness = prop_{mother} * shared_{mother} + prop_{father} * shared_{father} $ A female will share 50% of ...


7

Let's start with your definition. "Selection for traits that would be beneficial to a population of units at the expense of an individual unit possessing the trait" This is not a good definition of group selection. In reality, selection can act on groups regardless of the direction of selection at the individual level. This definition sounds to me (your ...


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 ...


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

is this guess proven or affirmed by science? It is a debated topic. Such altruistic behaviors (toward non-kin) are extremely rare evolutionarily, with some theorists even proposing that they are uniquely human [1]. Experimental evidence indicates that human altruism is a powerful force and is unique in the animal world. [...] Current gene-based ...


3

This is a relative thing in haplodiploidy system. r = Mother's side + father's side(in this case) D--Daughter S--Son F-Father M-Mother Note: You can get the below things from the question image itself.(All that you need to do is to read male and female appropriately as son,father,mother,daughter based on the context.So simple!) ...


3

It doesn't have to be that complicated. The evolutionary value of the offspring to the mother is half that of herself (0.5). Then the relative value of both mother and offspring is 1 + 0.5 = 1.5. So the value of preserving both lives is about 3 times the value of preserving the offspring alone, given the simplistic assumptions from the question. Therefore, ...


2

Relatedness measures a specific type of genetic similarity. In particular, it measures the genetic similarity relative to the rest of the population. When $r>0$, the recipient carries the actor's genes at a higher frequency than the population. When $r=0$ it doesn't mean that the actor and the recipient do not share genes; it only says that the recipient ...


1

I am not sure what you mean by "applies to numerous generations". If the following does not help, can you please clarify what you meant? Hamilton's rule expresses the condition for which, under a prisoner's dilemna game (see game theory), the stable equilibrium that will be reached is the one where everyone is cooperating. Hamilton's rule is, therefore, a ...


1

And above all, some of us are ready to forfeit their lives from their love to their enemies. This contradicts the survival instinct; such an absurd act cannot be explained with Darwin's theory. There are two problems with this statement, which make your question whether evolution might actually explain such behaviour, essentially meaningless: 1) The ...


1

There is another way to look at this question, which I suspect is even quicker (it is certainly more intuitive for me). Mathematically, it is identical to Mark's answer. If the parent chooses to not sacrifice herself to save the child, they have a net fitness of 1.5 (1 parent + 0.5 child) if they escape, and 0 fitness if they do not. Therefore, their ...


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 ...


Only top voted, non community-wiki answers of a minimum length are eligible