Why don't we evolve into microbes?

  • Thread starter Yashbhatt
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  • #51
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That's quite complicated.
 
  • #52
SteamKing
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What you mentioned is correct but a person with more sex drive tends to mate often and produce more offsprings. So, isn't that a survival advantage?
Yes, up until he gets the bill for supporting all his offsprings. Then, it's a decided disadvantage. Plus, he must keep all his baby mamas separated from one another lest it become a deadly survival situation for him from them.
 
  • #53
Borek
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But there is an obvious grain of truth in the idea.

I have read in several places (I believe I should be able to dig the original reference if that's necessary) that woman in general tend to be more promiscuous around ovulation, and are more attracted to macho types. There is an obvious advantage to that - kids of a successful wanderer (sorry, I can't think of a better English word) are more likely to be wanderers themselves, and to spread their genes widely. At the same time being less promiscuous and more faithful at other times keeps the supporting male close by, and makes the progeny more likely to survive.

The deeper you dig, the more fine print you find.
 
  • #54
Ryan_m_b
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But there is an obvious grain of truth in the idea.

I have read in several places (I believe I should be able to dig the original reference if that's necessary) that woman in general tend to be more promiscuous around ovulation, and are more attracted to macho types.
A lot of studies on the behavioural effects of the menstrual cycle, particularly with regards to sex drive and mate selection, are very dodgy methodologically speaking. Here's one meta-analysis that shows that the notion is unsupported:

Meta-Analysis of Menstrual Cycle Effects on Women’s Mate Preferences
http://emr.sagepub.com/content/early/2014/03/24/1754073914523073.abstract

This doesn't surprise me in the least. When it comes to evolutionary psychology there's a lot of bias masquerading as science as various groups (often inadvertently) just try to gather data to fit cultural ideas and place a far too heavy emphasis on explaining behaviour through biology.
 
  • #55
Borek
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A lot of studies on the behavioural effects of the menstrual cycle, particularly with regards to sex drive and mate selection, are very dodgy methodologically speaking. Here's one meta-analysis that shows that the notion is unsupported:

Meta-Analysis of Menstrual Cycle Effects on Women’s Mate Preferences
http://emr.sagepub.com/content/early/2014/03/24/1754073914523073.abstract
Thanks. I am not following these things closely, so my knowledge is based on popular science books, not on the original research. In my defense, authors like Matt Riddley (Red Queen) or Cindy M. Meston and David M. Buss (Why Women Have Sex) look credible, and I am more than sure it was either in one of these books, or in both.

This doesn't surprise me in the least. When it comes to evolutionary psychology there's a lot of bias masquerading as science as various groups (often inadvertently) just try to gather data to fit cultural ideas and place a far too heavy emphasis on explaining behaviour through biology.
Plus one on that. I am sure there are behavioral/psychological things that can be explained as evolutionary traits, but I agree the idea is often abused.

Unfortunately it is a loaded subject so I guess both sides play dirty tricks, instead of cooperating to find out what the reality is. Sigh.
 
  • #56
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Yes, up until he gets the bill for supporting all his offsprings. Then, it's a decided disadvantage. Plus, he must keep all his baby mamas separated from one another lest it become a deadly survival situation for him from them.
That's only for humans and not other animals.
 
  • #57
SteamKing
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That's only for humans and not other animals.
Yes, but in Post #49, persons were specifically mentioned, not animals. It's also not clear if animals have what is known as a 'libido', or if they are simply responding instinctively.

In any event, if a given population of a certain species of animals overpopulates, there are often dire consequences. The local supply of food can easily be outstripped by the expanded population, leading to starvation and increased mortality for those animals and others. Hardly a long-term survival strategy. If the animal population must migrate in search of food, additional risk may be introduced, in the form of increased predation, movement to less suitable environs, increased incidence of disease from animals weakened by starvation, etc.

This is often seen with deer populations in and around urban areas of the US. Local predators are driven out by human habitation, the deer are treated as non-threatening wildlife (the 'Bambi' effect), the local inhabitants may even wittingly or unwittingly provide food for deer living nearby, and fewer people are willing or able to hunt the deer. As a result, the deer will increase their numbers over time since there are fewer natural checks on their population growth, providing increased hazards to unwary people by straying into roadways or near homes looking for food.
 
  • #58
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That's only for humans and not other animals.
I can't think of a single species of animal with low sex drive.

Best, Henrik
 
  • #59
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It's interesting as well as saddening to see that what we think of various emotions, loyalty etc. are not as amazing as we think of them but are actually there because evolution favors them.
 
  • #60
Ryan_m_b
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I can't think of a single species of animal with low sex drive.

Best, Henrik

Animal sexual behaviour is extremely varied, as is parenting. Reproduction may occur at specific seasons, parental care might be involved in small numbers of offspring or not in many (so called R/K selection) and libido is not a constant factor but varies across development and in different environmental factors (libido drops off with age and can be affected by factors such as stress for example). Comparisons to humans are difficult due to the role sex has in socialisation (same applies to some primates).

Either way were really getting to the point where we're going around in circles. Getting back to basics: complex behaviours are rarely strongly associated with one trait which can be out under strong selective pressure. From now on it would be best if members start posting citations to research on this matter, paying very careful attention to the credibility of the papers (evolutionary psychology is a very controversial field).
 

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