Chimeras

[cringleman]

Touch

[Ruettiger]

I was under the impression that it was DNA that defined humans, as well as the ability to reason. However, I don't know if other animals can reason, I don't know how they think.

[cringleman]

Technically speaking, it is our genetic code that defines us as 'human' (Homo sapiens), but there is a massive amount of variation within the genes that separate us from our nearest relatives (we share a bit over 98% of our genome with chimpanzees). Looking purely genetically, it would seem that defining the categories of 'human' and 'not human,' there must be some number of differing genes that would cause a creature to be no longer human, but it is possible for someone to be born with such a high load of genetic defects as to be, under a strict binary distinction (of 'human' or 'not human'), defined as inhuman, despite the truth of the matter (or, correctly, dependent on your view).

 

The problem is that genetics simply provide almost too much data to be of use in the matter, and no one (to my knowledge) has ever even attempted to set out a guidline (which would, even so, be highly debatable), saying, 'If you lack X number of alleles from your code, you are not human.'

 

Also, 'reason' is a highly plastic term -- crows are able to solve fairly complex puzzles (as is my Jack Russell terrier), and Koko the gorilla could understand language (she'd have been taught an audible language if her vocal apparatus could have supported it), which further blurs the distinction.

 

You are, of course, roughly correct. We tend to have superior reasoning skills than most other animals (and, we assume, all other forms of life, like plants and algae and bacteria), and no one really knows to what extent (if any; scientists are loathe to admit any at all) animals can feel emotions. We are also different due to an inherent general genetic difference in our makeup.

 

It just isn't quite as simple as that sounds.