Once the egg is fertilized and becomes a zygote it is genetically unique.
(An ovum wouldn't implant. That would be a zygote.)
Ethics and morality in philosophy are generally based on minimizing the experience and perception of suffering, not promoting diversity - though diversity can certainly help reduce suffering.
Disclaimer: I have no expertise in the field of ethics and morality.
My girlfriend is however (has worked under Paul Bloom at Yale specifically in moral development, and is in a fully funded PhD program for moral development), and "minimizing the experience and perception of suffering" is not the "general basis".
Note: The author of the parent comment was not trying to make a moral judgement, but a biological and evolutionary one. That abortion is mathematically not beneficial - so there is no need to make a moral argument when there is a scientific one. (That is, not to say, that a moral one ought not be made.)
Certainly you can argue about a billion types of ethical frameworks, some of which may differ from this statement, and you can argue about the definition of ethics and morality. The prevailing basis of morality and ethics is most certainly minimizing suffering. Without sentient experience, ethics are meaningless. That's why in most frameworks we don't worry about the treatment of non-sentient things outside the context of the sentient experience of them, and we debate whether ethics apply to things based on whether they are sentient. Notwithstanding issues relating to these objects relationships to other sentient beings, we don't worry whether it's ethical to sit on a chair or pee in a toilet.
The parent comment was drawing an ethical conclusion from a biological fact, and certainly did not say anything about abortion being or not being "mathematically beneficial," whatever that means.
I am sure you were discontent with the summary, and had to scroll down to some other section which was closer to your bias.
I am also not sure how you can claim to know that the author /was/ drawing a moral conclusion, when he (just as you note about math) never said anything about it.
You asserted morality to trivialize his comment, I was merely pointing out the logical error in jumping from "biology and genetics" to "morality".
Throw morality out the door, and the point still remains.
I scrolled down to the part titled "Defining ethics," which happened to be the first section, thinking that would be applicable to defining ethics.
If you read author's comments in the thread, you will see he is clearly making the point that destroying a zygote is a moral issue, as he says:
> It's the destroying of a genetically unique individual human that is the issue
in response to a question about whether destroying a zygote is "wrong".
Throw morality out the door, and he is stating that a zygote is genetically unique for some strange reason in a thread about the morality of abortion.
Besides, his implicit point is also wrong - that a zygote is distinctive in being genetically unique. Each sperm is also genetically unique, so it's a rather inapplicable statement to the context of the thread, unless masturbation is also a sin against the universe.
I don't do much voting honestly.
> I don't understand how if one is viewing the subject from a evolutionary genetic perspective, why it is wrong to say that mechanisms that go against evolutionary development (abortion) are wrong
If anything goes against "evolutionary development" it is using technology to increase genetic diversity without regard to fitness.
Anyway, abortion does not go "against evolutionary development" any more than celibacy or monogamy.
Directed evolution is a whole different ball game that presupposes an active god or a detailed master plan. Either way, that is not evolution as most scientists would view it or as Darwin theorized. And regardless, humanity is not at risk of spoiling such plans.