less reproduction means less generation and less changes in species as well but certainly it consumes less energy.
An individual organism that spends no energy on reproduction (e.g. myself!) is not going to produce any offspring. I.E. I will not produce any offspring with the same trait of not spending energy on reproduction.
Whereas individual organisms that do spend a lot of energy on reproduction are likely to produce lots of offspring that also have the same characteristic.
Hence all existing species are abundant with individuals that have the inherited trait of spending a lot of energy on reproduction, and remarkably few weirdos like myself who prefer to spend their energy on other things!
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