Maximizing Genes: The Role of Natural Selection in Replication Success

  • Thread starter techmologist
  • Start date
  • Tags
    Genes
In summary, the conversation discusses whether natural selection favors genes that maximize their longterm growth rate or those that simply maximize the expected number of copies in the next generation. It is noted that since replication is a chance process, these are not always the same thing. The example of natural selection for size is given, showing that being the biggest may not always be advantageous. The concept of longterm growth is also questioned and it is suggested that it may depend on stable exponential growth and a high probability of the expected growth rate. However, it is mentioned that this is a speculative topic and may not have a definitive answer.
  • #1
techmologist
306
12
Does natural selection tend to result in genes that maximize their longterm growth rate (growth of the number of copies of themselves), or in genes that simply maximize the expected number of copies of themselves in the next generation? Since replication is a chance process, these are not generally the same thing.
 
Biology news on Phys.org
  • #2
techmologist said:
Does natural selection tend to result in genes that maximize their longterm growth rate (growth of the number of copies of themselves), or in genes that simply maximize the expected number of copies of themselves in the next generation? Since replication is a chance process, these are not generally the same thing.

Copies of themselves in the next generation. Genes have no way to predict the future.

Most species have gone extinct. Some species have gone extinct because of the long term consequences of their adaptation to short lived environmental conditions.

We may go extinct that way ourselves. However, history isn't done with us yet. So let us look at some other example.

A good example would be natural selection for size. Sudden catastrophes have tended to destroy the largest species of animals rather than the smallest. Having a huge adult size is an advantage under some short lived environmental conditions. While your biggest enemy is a member of the same genus as you are, being the biggest may be a deciding factor. When the meteor/magma flow/supernova comes, being large is not a great adaptation.
 
  • #3
Good points. The idea of longterm growth is not directly applicable anyway, since it assumes unchanging conditions and, in particular, resources that do not run out. However, if conditions are the same and resources are plentiful for many generations, I was wondering if natural selection might be able to weed out those genes that have a risky (high variance) strategy for getting into the next generation, even if the expected number of copies is higher than that for rival genes. Like you said, most species go extinct and their genes go with them. But some persist for a long time. I wonder if that is more than just good luck (or bad luck on the part of the species that went extinct, as when the conditions change abruptly).
 
  • #4
Perhaps we should define how many generations define longterm?
 
  • #5
enosis_ said:
Perhaps we should define how many generations define longterm?

I wouldn't know how to give a number, but here is what I have in mind. Long enough for a stable exponential growth to set in. Enough generations so that the long term growth rate becomes nearly equal to its expected value with high probability (law of large numbers).
 
  • #6
Sorry, this violates our rules against overly speculative posts.
 

1. What are selfish genes and how do they influence behavior?

Selfish genes are a concept proposed by evolutionary biologist Richard Dawkins in his book "The Selfish Gene". They refer to the idea that genes are the primary unit of selection in evolutionary processes, and their main goal is to ensure their own survival and replication. This can influence behavior by favoring traits that increase their chances of being passed on, even if it may not benefit the individual organism.

2. How do Kelly bets relate to selfish genes?

Kelly bets, or the Kelly criterion, is a mathematical formula used to determine the optimal amount of money to bet in order to maximize long-term growth. In the context of selfish genes, this theory suggests that organisms should make decisions that maximize their expected reproductive success, instead of focusing on short-term gains. This can be seen as a manifestation of selfish genes, as they are prioritizing their own replication over individual survival.

3. Can selfish genes explain all aspects of human behavior?

No, while selfish genes may play a role in shaping behavior, they cannot fully explain all aspects of human behavior. Evolution is a complex process influenced by various factors, and behavior is also influenced by cultural, social, and environmental factors. Additionally, humans have a level of consciousness and free will that can override genetic impulses.

4. Are selfish genes inherently "selfish"?

The term "selfish" in the context of selfish genes does not necessarily mean that genes have conscious intentions or desires. It simply refers to the fact that genes are focused on their own survival and replication, rather than the well-being of the individual organism. This can be seen as a survival mechanism that has been favored by natural selection.

5. How can the concept of selfish genes be applied in practical settings?

The concept of selfish genes can be applied in fields such as evolutionary biology, genetics, and behavioral economics. It can also be used to understand and predict certain behaviors, such as risk-taking and decision-making, in humans and other organisms. However, it is important to note that this theory is just one aspect of understanding behavior and should not be used as the sole explanation for complex behaviors.

Similar threads

  • Biology and Medical
Replies
1
Views
1K
Replies
12
Views
1K
Replies
3
Views
2K
Replies
2
Views
3K
  • Biology and Medical
Replies
1
Views
1K
  • Biology and Medical
Replies
1
Views
1K
Replies
12
Views
2K
  • Biology and Medical
Replies
14
Views
4K
  • Biology and Medical
Replies
1
Views
1K
Replies
16
Views
2K
Back
Top