Tuesday, January 09, 2007

It's a fact: an embryo is a human being

Mike at Keeping up with the Blogses wrote:

I refer to a "discussion" I had on a messageboard with someone who said that using embryos or other bits of human material for research was "murdering" a "human being". Absolute bullshit. That's like saying a sparkplug is a car. Humans are - barring disabilities that stem cell research might help overcome - walking, talking, reasoning structures comprised of billions of cells and numerous organs all of which function together. A bit of tissue in a petri dish is not a human being.

That may be his subjective definition of a human being.

But it's not a scientific one.

By the laws of science, we know that human life begins at conception. The zygote is a distinct organism. A zygote moves, takes in nutrients, has his own morphological structure and grows. By that measure, he lives up to the definition of an organism.

So what kind of organism?

An organisms can be classified by their genus and species. Zygotes that are the product of two human gametes can't be anything else that members of the species homo sapiens. It's a law of biology. I remember it's one of the first laws I learned in high school biology: when two individual of the same species reproduce, their offspring will be a member of that species.

A sparkplug may not be a car, but a zygote is a human being. That's a scientific fact.

And I know the objections that will be raised:

* A zygote doesn't look anything like a human being.

Well caterpillars don't look like butterflies and tadpoles don't look like frogs, but they're one and the same species.

* If a zygote is a human being, then so is a sperm, so masturbation is murder.

This has got to be one of the most obtuse responses to the claim the zygote is a human being. What this is, is not an argument. It shows the person making the argument isn't even trying to understand the scientific issues at stake. They just want to make notion of a human zygote seem stupid, so they make this obtuse comparison, hoping to sidestep real scientific discussion. When a person comes up with the "masturbation is murder" argument, in my mind, he's lost the debate. In fact, it shows he can't debate at all.

* A zygote is too small to be a human being.

Size isn't the issue. The zygote's internal organization is such that as he grows his body develops the organs that we see in newborns. Development is not a sign that a zygote is not a human being-- in fact, it's the very sign he IS. Tadpoles are small compared to full-sized frogs, but that doesn't make them non-frogs, either.

* A zygote is no more human than a skin cell.

Again, this shows a lack of ignorance of biology. A skin cell has one function. Its function is to build skin tissue. It's one cell.

A zygote does not stay at the one cell level very long. His cells multiply. He grows many kinds of cells: heart cells, liver cells, and so on. There is cell specialization.

If nothing else, people who do not admit the personhood of the unborn should at least admit the scientific facts.