Where did we come from?

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No, this isn't about your mummy's tummy. That's ontogeny, whereas I'm here to talk about phylogeny.

Err, what's all that?

Sorry! Think of ontogeny as your history in your lifetime. Think of phylogeny as your history before you were born, not just the history of your people, community or nation but the history of your species, genus, family.. the history of long, long before.

Why is this post here in the first place?

There is an ongoing debate about whether or not modern humans (Homo sapiens) drove out a hobbit-like species (Homo floresiensis) from Indonesia, to extinction.

Yes, I said "hobbit".

Homo floresiensis, female.
Reconstruction by John Gurche.
Image from Smithsonian NMNH website.


I believe you're piqued as well now.

You might have heard several similar-sounding terms:

We're all monkeys, we're all apes, we're all primates.
Homo, hominids, hominins, hominoids.
Neanderthals, modern humans.
Blah blah blah.

HUMANS FOR DUMMIES !


I'm not a paleoanthropologist.
So this is, most emphatically, not a scientific report. It's an outreach article written by someone who herself knows very little about this area but is very very excited about it, for people of pretty much the same description. You and I are going to start from scratch, try to understand what's going on, and hope to explore enough to sound super-cool in front of our fellow humans.
Like, make them look like total monkeys.
Kapish?
:D

SO HOW DID WE GET HERE?

There's just this one teeny-tiny piece of homework you need to do before we can start with the cool stuff. (And I've even done it for you!)

Biologists group living beings using a hierarchical classification system. It was born in the head of Carolus Linnaeus, a Swedish scientist, but has undergone some changes since then.

First column shows the original Linnaean system. Colored levels show changes from previous system.



This is the language we will be using all throughout this post, and once you can get over the big words, you'll see how beautifully this hierarchy will show you the pathway of human evolution.

NOTE: Classifications (or "taxonomy") are constantly under revision or debate, based on new evidences. We're approaching this topic in a not-100%-scientific-way, which is easy to begin with but might not all be correct. If you find inaccuracies, please feel free to point them out to me.

We begin at the highest levels of the classification: the domain or empire, and then the kingdoms. Indians normally follow the 5-kingdom classification which most of us have studied in high school. We're all eukaryotes, which means we have relatively advanced cells. We're all animals (as some of us make quite painfully obvious every now and then).


 
The colored words in each list show where we belong on that level of classification. The bottom bar places all important big and complicated words in one place so you don't have to remember them.




We belong to a subkingdom that is divided into two groups: one group has radial symmetry whereas the other has bilateral symmetry. It's easy to guess that we're not the radial ones! Having bilateral or 2 types of symmetry means we have  2-way symmetry in our bodies - a front and a back, a top and a bottom. Try thinking of this the next time you stare at someone's posterior.
:P

 

Note that we're a part of a phylum of chordates. This term refers to the presence of a somewhat primitive nervous system.






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