dirtyparrot
Upholding Brannigan's Law
- Joined
- Oct 6, 2005
- Messages
- 1,841
And yet bacteria are undisputed masters of this planet. Speaking of that, I'm kind of surprised that the OP's list lacked the origin of the eukaryotoic cell (perhaps more improbable than life itself?). And it's not as if sexual reproduction is the only way more-complex life could work -- bdelloid rotifers demonstrate that.
There's no doubt a major benefit to sexual reproduction when faced with multiple stressers at once. A subset of that, Red Queen is also well supported. I remain skeptical that this truly outweighs only contributing half yourself to offspring. To me, halving yourself only makes sense with long-term foresight. Else, you're not going to benefit from the potential of running into multiple stressors in the present where you're under limited stress.
At the outset, it doesn't require any more energy than a female making an egg. It may require more energy after offspring are born, since only one parent is there to feed / defend them.
Bacteria are the masters because of their short generation times allowing numerous cracks at hitting the lotto. Mosquitoes and other pests to a lesser degree display similar abilities to adapt probably for similar reasons.
There may be no choice but to produce haploid sex cells in order to maintain the "right" number of chromosomes. There seems to be very little allowance for more or less than the "right" number of chromosomes. Based on what we know, if 2N became 4N, 4N became 8N, ..., this generally does not end well.