Where did we come from? Part III

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In case you want to go back to Part 1 or Part 2. (But you don't need to!)

 No, you absolutely don't need to revise or remember anything from the previous 2 posts. Here's where we left off:

And all you really need to remember is the key words at the bottom of the image.
  • We're all eukaryotes => have an advanced cell structure
  • We're all animals => have the ability to "move it!"
  • We're all chordates => we have a convenient nervous system
  • We're all mammals => we have mammary glands and hair
  • We're all primates => we have complex brains and grasping hands

MOVING ON

So, with the advantages of several ancestors, we made it to the group of advanced primates which are divided into the tarsiers, the new world monkeys, the old world monkeys and the apes. The last 3 (Happlorhines minus the Tarsiers) are also collectively called the simians or anthropoids. Humans fall under the Superfamily Hominoidea, and hence are also referred to as hominoids.



The apes (Superfamily Hominoidea) are further divided into the Greater Apes and the Lesser Apes. Needless to say, the most advanced species on this planet falls under the "Greater" category, which also contains orangutans, chimpanzees and gorillas apart from humans. This "greater" category is what is called the Family Hominidae and thus, we are also called the hominids.

Let's pause for a moment and look at our family.
  • The hominids are probably the most advanced family in the world. Members of this family are fairly intelligent beings, and even chimpanzees have been taught sign language.
  • If we were to have a family picture with one representative from each species, there would be only 7 members in the picture. There are only 2 living species of orangutans (the genus Pongo), 2 of gorillas (the genus Gorilla), 2 of chimpanzees (the genus Pan) and 1 of the humans (the genus Homo).
  • Some deceased (extinct) members of this family belong to the genera (singular: genus) Australopithecus, Paranthropus, Sivapithecus, Gigantopithecus and Ardipithecus.
If we get more exclusive and drop the not-so-glamorous orangutans, we arrive at the concept of the Subfamily Homininae (getting us the title of hominines).

An orangutan

Why did we get sassy with the orangutans? Well, it turns out they got sassy first. The orangutans "drifted away" from the great apes about 14 million years ago, and the great ape lineage got divided into two ever after. Humans evolved much later from the original lineage, and thus became hominines.



Things seem to be getting trickier as the successive rounds to qualify to be a human get tougher and tougher. The Subfamily Homininae which includes the humans, gorillas and chimpanzees is divided into two tribes: the Hominini (which is why we're called hominins) and the Gorillini. 


A gorilla
Although I wouldn't want to pick a fight with that big guy, we're still going to exclude him from our even-more-exclusive Tribe Hominini. This tribe is further divided into some subtribes, which might seem like a super-tortuous way of getting to be a Homo. However, it is this level of detail that tells us that humans are more closely related to the chimpanzees, than to the gorillas, than to the orangutans, than to the gibbons, than to the monkeys.

The Tribe Hominini is divided into the subtribes: Hominina, Australopithecina and Panina.
Panina contains the chimpanzees:

A chimpanzee

And Australopithecina are all dead. But we're going to dwell on them for a moment. Because of Lucy.

Lucy
Lucy happens to be a "marvelous" specimen of an Australopithecan species, discovered in Ethiopia in 1974. For someone who died about 3.2 million years, she sure got abnormally famous, having dedicated exhibitions and numerous replicas around the world.

When was the last time you met someone who got their name out of a Beatles song anyway?




 



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