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If a species has a high mortality/birth rate, then it is able to adapt to changing environments more quickly than species that live for a long time.

Without a high mortality rate, food and other natural resources are hogged by previous generations and the gene pool is polluted when less evolved, older animals reproduce.

Because of this, wouldn't it make sense to conclude that a high mortality/birth rate is better for a species as a whole? This advantage could snowball out of control, because faster evolution would lead to superior reproduction methods which would lead to faster evolution etc...

If this is true, then why are mice not more successful and adapted to their environment?

  1. House mice were chosen because of their high birth and mortality rates.
    Birth rate: "Approximately 6 mice can multiply into more than 60 mice in 3 months." http://www.crittercatchersinc.com/critters/Mice/Mousereproduction.html
    Lifespan: 1 year http://themysteriousworld.com/top-10-shortest-living-animals-in-the-world/
  2. One of the reasons these traits may be more harmful than helpful is that predators benefit from a population increase. I managed to find this article in my research:
    http://www.ncbi.nlm.nih.gov/pubmed/12675374
    Feel free to include this source in your answer if I have interpreted it correctly. The reason I am posting this question answerless is because I am not sure enough about the conclusions I have drawn to answer it on my own and (mostly this) because I am very interested to see what other disadvantages this evolutionary strategy would have.
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The first part of the question is interesting.

Does an increased reproduction/mortality rate provide an evolutionary advantage?

The concept of evolutionary advantage for a species needs to be used with much cautious as different definition of evolutionary advantage may exist. You should typically have a look at game theory beforehand to understand the issue of definition.

A species that have shorter generation time tend to respond faster to new selection pressure (even more so in species that have short generation time and also have high population size).

why has humanity not been enslaved by mouse¹ overlords with superior intelligence and adaptations to suit the environment perfectly?

You seem to be viewing intelligence and/or species competitive ability as end goal of natural selection which suggests important misunderstanding of how evolution works.

One of the reasons these traits may be more harmful than helpful is that predators benefit from a population increase

You might want to have a look at the post What prevents predator overpopulation?

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  • $\begingroup$ "You seem to be viewing intelligence and/or species competitive ability as end goal of natural selection which suggests important misunderstanding of how evolution works." It was a joke, but since it is detracting from the quality of the question I will remove it. Sorry about that. $\endgroup$ – DivideByZero Jul 13 '16 at 4:09
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1) Reproduction is metabolically costly, so a high reproduction rate, such as that seen in fishes that lay thousands of eggs at a pop, is generally a strategy to compensate for a high mortality rate. On the other hand, bacteria, that can in some cases double every 20 minutes, have the advantage of rapidly evolving resistance to antimicrobial agents.

2) Primates and elephants are examples of successful species that have a very low birth rate. The biological investment here is in nurturing and protecting offspring for many years to reduce mortality and to transfer cultural knowledge to the next generation to improve reproductive success and community success. In the case of humans, long lifespan, even beyond reproductive age, is an advantage because the older generations can help care for children while the parents work, and they support the community through leadership and by imparting to younger generations a lifetime of cultural knowledge. Unfortunately, the very success of humans may lead to its ultimate downfall, due to overpopulation and environmental degradation.

3) Mice are successful because they eat our crumbs and our crops, and take refuge in our shelters. So, in a sense they have enslaved us: we work for them without pay or benefits.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3353347/

https://frontiersinzoology.biomedcentral.com/articles/10.1186/s12983-014-0054-0

http://www.cell.com/trends/ecology-evolution/fulltext/S0169-5347(15)00104-4

https://en.wikipedia.org/wiki/Grandmother_hypothesis

https://en.wikipedia.org/wiki/House_mouse

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  • $\begingroup$ Please add some citations in your answer, lest it is likely to be downvoted and removed. $\endgroup$ – another 'Homo sapien' Jul 13 '16 at 5:27

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