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Well, are we? You’ll note that I didn’t call this article, “did we evolve from apes?” or “Are we related to apes?” No, I simply want to ask whether modern humans ARE apes. Now science has a clear answer to this question (YES!!!) but I’m going to need a bit more than a one word answer to substantiate that claim. Before the comment war starts I want you to read what I have written below as I’m going to approach this question from both a morphological (physical characteristics) and genetic viewpoint.
Morphologically speaking
A morphological classification concerns grouping similar organisms by way of shared physical traits. For example, nobody (not even dumbwin) would argue that humans aren’t mammals, why? Because we have hair, our females lactate, we are warm-blooded (endothermic), have a four-chambered heart, a single dentary bone connected to our skull, and the list goes on here: http://animals.about.com/od/mammals/p/mammals.htm.
Any name that we give to an organism works by grouping it with other organisms via shared traits. If an organism gains a trait (such as dinosaurs developing wings) then that organism branches off the classification to become a new group (in this case birds) however they are still grouped with their ancestors (yes birds are considered modern dinosaurs). Creationists should recognise this as similar to their ‘kinds’ theory however instead of there being distinct kinds science classifies organisms on different levels, so whilst a gorilla is an animal, it’s also a mammal, it’s also an ape and it’s also a gorilla (there are more than one species).
So are humans apes? Well just like mammals, apes have distinguishing characteristics such as hair and mammary glands but they also display unique characteristics such as the lack of a tail, a specific dental formula, giving birth to helpless young on top of their mammalian features which allow scientists to call an animal an ape. Humans fit very neatly into the ape classification model although we too have distinct differences such as bipedalism and I’m sure you’ve heard us described as ‘the naked ape’ before. Just because we have deviated from the ‘holotypical ape’ doesn’t mean that we cease to be apes, in fact every extanct ape species has unique traits hence why we use species models to distinguish between organisms.
Now I can hear the murmurs already that just because something resembles another organism it doesn’t make them closely related, what about convergent evolution? Well this is where we use genetics J
Genetically speaking
I decided to write this article after encountering yet another 2% debate on the forums. Is a 2% difference between chimps and humans a large or small gap? It obviously is a significant difference although sometimes I do wonder when reading these forums. Let me explain like this; the closer related you are to something, the closer your genome will resemble that organism’s. That makes sense; my brother’s genome is more similar to mine than an Eskimo’s yet all three of us are related because we shared a common ancestor. My brother and I are so similar because our most recent common ancestor is our mom but we’re different from our chilly friend because our common ancestor is much further back in our genealogies and thus there has been more time for variation to be added to my and the eskimo’s genome. Greater time since the common ancestor will equate to a greater genetic difference between two organisms. Chimpanzees (Bonobos in particular) are our closest non-human relatives and our common ancestor was an ape, ergo we are apes too.
But why do all the other apes have 48 chromosomes yet we have 46? Chromosomes are the way (eukaryotic) cells package their DNA. They are clumps of DNA. 46/48 equals 95.8% not 98% so what’s going on here? Well if our ancestors had 48 chromosomes how did we get 46? Well 48 chromosomes are actually 24 pairs (one from mom and dad) so somewhere we’ve lost a pair of chromosomes. Simple, let’s go look at the chromosomes. The difference we see is that humans have an extra-long chromosome (chromosome 2) to the chimp’s extra pair. With a bit of logic we can deduce that the two extra chromosomes of our ancestor at one point conjoined, thus we have an explanation for the extra-long chromosomal pair that we see in humans. Great hypothesis right, but where’s the proof? It’s right there! Each chromosome ends in genetic material called telomeres but in chromosome 2 there are 3 locations where telomeres are found, one on each end of the chromosome but also smack in the middle! The only explanation for this is that two chromosomes have recently joined together! BOOM! For a far more eloquent explanation check out the youtube videos on the subject or visit http://en.wikipedia.org/wiki/Chromosome_2_(human). It’s all there with pretty pictures.
Using both morphlogy and genetics we have identified our place in the tree of life. A creationist would quite happily accept humans to be vertebrates and mammals but dare say that we are animals or apes and suddenly we’re immoral beings. Guys, vertebrates are animals and mammals are animals. We do not exist outside of zoological classification; WE ARE APES. Stop getting so insulted by the idea and look at it logically.
