Any Biologists In The House?

Started by Calin Leafshade, Mon 24/01/2011 09:08:36

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Calin Leafshade

There is a discussion that has been had on IRC once or twice and I would like to clear up the answer since I dislike being in doubt about anything.

I asserted that we (humans) can still be classified as monkeys. I give the following reasons for my assertion: (be prepared for spelling mistakes, i'm not looking up every technical term)

First i will draw the relevant part of the phylogenetic tree:

Code: ags

				   Cercopithecoidea
				/
		   Catarrhini
		/		\
Anthropoidea -- 		   Hominoidea
		\
		   Platyrrhini


Usually Cercopithecoidea are categorised as 'Old World Monkeys',  Platyrrhini are 'New World Monkeys'. and Hominoidea are Apes. Anthropoidea are also often labelled as 'monkeys'

Now, sometimes (and originally I believe) Catarrhini was classified as 'Old World Monkeys' this was until it was discovered that Hominoidea belonged to that clade. The OWM tag was then moved to Cercopithecoidea specifically to exclude apes. However if you do this then two monkey clades  (Platyrrhini and Cercopithecoidea) are separated by a clade which is *not* classified as monkey and thus this makes monkeys scientifically paraphyletic which is frowned upon in cladistics since it makes the term useless.

Monophyletics however would say that all humans are apes and all apes are monkeys thus all humans are monkeys.

So bottom line - One of the following must be true: 1, 'monkey' is a meaningless term and the whole thing can be disregarded (although you would probably have to do the same thing with 'Ape' and countless other words.), 2, 'Monkey' can be applied to anything in Anthropoidea which would make us a monkey or 3, I have made a mistake somewhere and need to be corrected by a biologist.

My source is this:

http://www.youtube.com/watch?v=QT4Gnt1Ku4Y

I know it's only a youtube video but it seems well sourced and verifiable (I have found multiple references to Catarrhini being referred to as OWM)

The problem I have in verifying this is that (as the video states) there is a huge resistance to this amongst conservative scientists since the idea of referring to a Human as a monkey seems insulting. Consequently alot of outdated literature refers to the OWM as Cercopithecoidea so I need an up to date opinion from an actual biologist.

Come on we must have ONE qualified biologist (or someone in a related field) amongst us.


uoou

It's just taxonomy and when you get right down to it it's all quite arbitrary/conventional. I could, if I could be arsed, which I most surely cannot, devise a taxonomic system which classifies humans as cups. And so long as that system is internally coherent then no one could really argue against it other than to offer a preferred, equally valid taxonomy.

The purpose of a taxonomic system is to allow biologists to talk about things rationally. Beyond that, it's all meaningless.

uoou

From our discussions on IRC I see I've missed the point. Ignore my previous answer. Also ignore my currently untrimmed beard. Thanks.

Misj'

Before I begin, in Dutch there's no difference between a 'monkey' and an 'ape'. They're both 'aap'. From a scientific point of view it's just a name someone once gave to a certain family of animals...it's just a word. And to quote Shakespeare: What's in a name? that which we call a rose - By any other name would smell as sweet.

So...back to biology...

The first things is: we might need to correctly define species (maybe we don't, but I already wrote down this part and I don't feel like removing it again). The most common definition used is: two individuals of opposite gender that can produce fertile offspring. There is a huge problem with this definition since it technically originates from a time when for some reason many people believed that the world was static over time (well, scientists believed that, most common folk had more sense). To explain this problem take the following story:

Jack, Jill, and Jane (each of whom fully represent their population/race) are walking down the street. Jack can mate with Jill to produce fertile offspring, and similarly Jane can mate with Jill to produce fertile offspring. However, Jack and Jane can mate but this either produces no offspring or it's not fertile. Within this example, they are all of the same species (since Jack and Jill are, and Jane and Jill are...so it's possible for genetic material to next generations and mingle etc). So they're walking there, when suddenly a car comes around the corner. Jack and Jane manage to jump to safety, but Jill is hit. She dies...and suddenly the situation has changed, because genetic material cannot be exchanged between the Jack and the Jane race; so they suddenly became of a different species while this morning they weren't yet.

Of course this is a huge over-simplification, but it shows a biological problem with the definition of species, and one of the reasons why certain people prefer to use genetic resemblance as a marker (but it's a fuzzy marker that is still not clearly defined). At this point I do have to make a biologists' joke: Men and apes only resemble each other 97% genetically, while men and women resemble each other a whopping 95%!

That being said, back to the problem: could one - from an evolutionary point of view - characterize a species by its ancestor. Truth is: we do this all the time, we talk about animalia, verterbrates, omnivores etc. Each of these definitions group branches by common features, and the same would be true when using 'monkey'.

So that gets me to the other point: 'there is a huge resistance to this amongst conservative scientists since the idea of referring to a Human as a monkey seems insulting'. I very much doubt that: we refer to humans as animals, as vertebrates, as primates, etc. There is little resistance to that (it's merely a biological definition/taxonom, if we decide to rearrange the whole thing (and every now and then we do) that doesn't change anything, because in reality taxonomy has little value to most biologists' actual work). Personally I would in this case refer to humans as either primates, simians or alternatively Hominidae (great apes)...but if you want to refer to them as monkeys that's fine by me. It's just confusing to the English speaking population and in an argument therefore better avoided to better focus on the point you're trying to make.

Ps.  both 'monkey' and 'ape' are indeed meaningless terms (which is why we don't really make that distinction in Dutch (and several other languages)).
Pps. no I didn't watch the youtube video...

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