Lucy the Australopithecus Afarensis - IAC Training Video

Lucy as an Icon of Human Evolution

Lucy is probably the most famous fossil hominid. It's one of the main icons of human evolution. Now wherever you go Lucy is usually portrayed as being an upright-walking, half-human, half-ape-like creature.

She's usually shown with whites in her eyes, shown as being very human-like, but what the public is usually not told is how ape-like Lucy really was. Here we have a replica of Lucy's skeleton. It was discovered back in 1974 by Donald Johanson and it was not complete.

It was only about 40 of the skeleton. It's missing most of the hands, most of the feet, as well as most of the skull. Her entire body was about three and a half feet tall and she probably weighed around 60 pounds.

Now her scientific name is Australopithecus afarensis. Australopithecus means southern ape and afarensis refers to the Afar region where Lucy was discovered. You can use Lucy's skeleton to show your audience what Lucy really was, an ape, and you can also use it to show how data in this field of paleoanthropology can often be very fragmentary.

Oftentimes what happens is when there's a limited amount of data, imagination tends to take over and that's what's definitely happening in the case of Lucy. Now more than just Lucy has been found of Australopithecus afarensis, about 400 different specimens have been discovered, but most of these specimens are very fragmentary.

35 of them are just teeth. So when showing your audience how few specimens of Lucy's kind we actually have, you can use this little bag of bones we have here as kind of a visual representation. It's not a perfect representation but it just kind of gives them an idea of how many of these specimens have actually been found.

Lucy’s Skull and Ape-Like Features

So what I'm gonna do for this segment is I'm gonna show you Lucy's anatomy from head to toe and show you that Lucy was just an ape. So let's take a look. You'll notice here Lucy's skull was mostly missing.

There's only a few fragments of Lucy's skull. Here's a reconstruction of Lucy's skull which is also part of the collection. You can use this when showing how a lot of the times when we dig up fossils of creatures that are claimed to be man's ancestors, the evidence is very fragmentary.

The brown parts are what was actually discovered. The white is all filler. Now we have more skull material today and this skull over here is actually a reconstruction of what the Australopithecus afarensis skull would have looked like complete.

Now no actual 100 complete skulls have been found but this kind of gives you an idea of what the whole skull would look like. Now if you were to use one word to describe this skull, ape-like would be a good word to use.

Here you can see the slope of the face. Apes have very sloped faces. Humans have very flat faces. Here you can see this afarensis skull compared to that of a modern-day bonobo which is a cousin of a chimpanzee.

You can compare them side-by-side and they actually look quite a bit like each other. Now that doesn't mean that Lucy was a bonobo or a chimpanzee but compared to a human, the afarensis skull looks much more like a bonobo or a chimpanzee than a human skull.

Something else that's important to talk about when talking about Lucy's skull is that Lucy's inner ears, specifically the semicircular canals which control balance, are very much like those of an ape.

Now what this indicates is that Lucy didn't necessarily have the balance of a human being which indicates that she may not necessarily have been able to walk in a human-like manner. So next let's take a look at one of Lucy's little vertebrae right here.

This here is a thoracic vertebra. It's one of the vertebrae of the trunk area and this particular vertebra was believed to have belonged to Lucy for about 40 years until recently it was actually discovered to belong to an extinct baboon.

So it's just another reminder that scientists are human. They can make mistakes and sometimes those mistakes can take a while to be corrected. The next part we're going to take a look at is Lucy's scapula and one thing that you need to know about this scapula and something you can point out to your audience and showing that Lucy was just an ape is that in humans the point where the scapula articulates with the humerus called the glenoid cavity is pointed more towards the side.

So in my scapula the glenoid cavity right here is more pointed that direction whereas in apes the glenoid cavity is more pointed that direction. Now in Lucy's species the glenoid cavity was pointed more upwards like an ape which would have allowed it to climb easier in trees.

So that's something you could point out to your audience when showing them Lucy's scapula. So now let's take a look at Lucy's upper arms. Here is her right humerus and her left humerus. Now a recent study on Lucy's upper arm bones revealed more evidence that Lucy was a tree climber.

A CAT scan on her upper arms showed that her arms were more heavily built than her legs which indicates that Lucy was spending a lot of time climbing in trees. Now when you compare these two upper arm bones you'll notice that they are differently shaped.

Her right humerus is smashed inward. Now scientists have recently done some studying and have found that it actually has a compression fracture. Now the scientists doing the research believe that this is because Lucy died by falling out of a tree.

They say that when someone falls from a large height the person will land on their feet and stretch out their arms to break the fall but then when they land on the ground it's going to compress the upper arm into the shoulder which will cause a compression fracture and that's what we see here in Lucy.

Lucy’s Curved Fingers, Pelvis, and Upright Walking Debate

Another feature we can talk about when talking about how ape-like Lucy was is her fingers and toes. Here is one of her finger bones and here is one of her toe bones and when you examine them you see that they are in fact curved which is a feature typically associated with apes and apes have curved fingers that allow them to grasp tree branches to climb and so this is a very ape-like feature in Lucy that indicates that Lucy was indeed climbing in trees.

A very ape-like characteristic. Here is Lucy's pelvis. This is her iliac blade here and here is Lucy's sacrum which is the second to last part of her vertebral column. They fit together at what's called the sacroiliac joint.

Now as Lucy's pelvis was originally discovered the front part of her pelvis juts out at a straightforward angle and so it's really not the way Lucy's pelvis would have likely have gone in real life. In both chimps and humans the front part of the pelvis connects together down more like this.

So what scientists did is they reconstructed Lucy's pelvis. Specifically Owen Lovejoy reconstructed the pelvis as being more bowl-shaped like a human being so that she could walk upright. But other reconstructions have been offered.

Christine Burge published a study in the Journal of Human Evolution showing that Lucy's pelvis may have actually had a shape that would have caused the gluteal muscles to attach to the pelvis in such a way to make it so that her legs would have not been held stable like a human's legs in upright walking.

So even if Lucy did walk upright it wasn't in a human like manner. She would have probably wobbled around and had an awkward gait. So let's talk for a minute here about Lucy walking upright. Now you hear different people say different things.

Some creationists believe Lucy was a knuckle-walker. Some believe she was an upright walker. But pretty much all creationist scientists agree that Lucy was just an ape. When evolutionary scientists look at Lucy they have an idea in their mind about how evolution is supposed to have happened.

They believe that a knuckle-walking ape-like creature gradually evolved over time into an upright walking human. So when scientists come to a creature like Lucy and they claim to find evidence of upright walking, they're going to interpret that evidence within their worldview.

It's not about the evidence, it's about the interpretation of the evidence. Now that we've taken a look at some of the substance that you can mention when talking about Lucy's skeleton, I'll just tell you a couple tips you can use for displaying Lucy.

Displaying Lucy for Teaching

So the first way you can display Lucy is as I have Lucy here. You can lay her bones out and in her anatomically correct position. But just be warned that it will take you some time to set up Lucy's bones.

The second way you can display Lucy is to have her bones all in a single box and pour it out on a table so you can show your audience that there really wasn't a whole lot of Lucy discovered. And remember that Lucy is actually a pretty good skeleton in terms of the quantity and completeness of the bones.

Most specimens in the field of human origins are only teeth or jaw fragments, so this is a pretty good specimen. But even considering that, it's really only a few bones and scraps of bone. So enjoy using these teaching objects as you seek to bring God glory by showing people that His Word can be trusted and that the creation confirms it.