Liang Bua represents the whole sequences of the prehistoric times– from Palaeolithic, Mesolithic, Neolithic, until the Paleometallic. And we found here all of them. We found Stegadon, an extinct elephant. And also we found komodo dragon. They’re still living here on komodo island. And another thing we’ve found also there the giant stork– Marabou stork. But other area already extinct all for 200,000 years ago, but still exist here. Stegadon remains here are very young compared with other sites in the world.
These faunal remains have just come from our wet sieving station, where the sediments are taken after we’ve excavated them. And we basically recover many small bones and teeth of animals that otherwise, because the sediment is very sticky and clay-like– and it doesn’t go through a regular sieve if it’s just in a dry form– so we use water to help that process. And so here we have a number of faunal remains from roughly about 3 and 1/2 metres depth, which is in the Early Holocene sequence. So again, these would be animals that are associated with some of the earliest modern humans that were living in this area. [INDONESIAN] OK. This is a lower jaw fragment of a fruit bat.
And you can see that it’s missing some of its teeth, but it still has one of the teeth in. That’s very diagnostic of those species. So these are the large fruit bats. And again, this is a lower jaw of a giant rat. The giant rats are endemic to Flores, meaning they’ve been here for a long, long time. And these rats in particular are roughly about 3/4 of a metre long from nose to the end of the tail– so much bigger than most cats or dogs that you might have at home. This is a thigh bone, again, from a species of giant rat.
So you’re getting a picture that we actually find of a lot of giant rats in the sequence here. This again is a lower jaw fragment, again of a rat, but a very small rat. And that’s one of the interesting things about Liang Bua is we actually have lots of evidence of very small rats, medium-sized rats, all the way up to some of the biggest rats that live in the world. Liang Bua is really special. It’s this rat cave. A few of us nicknamed it the rat hotel because over 70% or more of the assemblages are rats. They come in all different sizes and live in different ecosystems around the island.
So in combination with the Stegadons and Komodo dragons and some of the more larger fauna, the smaller guys– the smaller fauna– has a much more higher resolution throughout the sequence. So if we can figure out which ones are where, where do they occur in combination with– associations with other stone tools, possibly or with floresiensis itself, then we can maybe figure out why they’re there. I’m specialised in fossil birds. So I look at all the fossil bird remains that we find at Liang Bua, and I try to put together what the bird fauna looked like at Liang Bua, both in the very old layers, as well as the young layers.
It still very much comes down to looking at things— either with naked eye, with microscopes, or with other techniques– and also comparing material. Like what does this look like? What does that look like? When we are looking at cut marks, for instance. What are the differences between the various tools used? Or how can we identify human tooth marks from Komodo dragons or any other type of animals? So it very much comes down to seeing patterns. So we’re going to be looking at things like cut marks to see if there’s any direct evidence of, say, like a stone tool cutting, disarticulating small mammals– especially the rats– to see if they were actually consuming them as part of their diet.
This is a vertebrae of a snake that you can see it’s very black. It’s been burned before it was deposited into the sediments. This is evidence that in the past, the people at this time– it was likely common for them to eat not only the giant rats, but also snakes. Many species that we find in the old layers– the hobbit layers– we still find today on the island. So they have not gone extinct. But there’s a number of species that are no longer present today– and those include a giant stork and a vulture. And those are unusual because they’re very big birds, especially the giant stork, that seem to have been closely associated with Homo floresiensis.
And their absence today signals that that whole ecosystem of Homo floresiensis disappeared all at once. We see the Marabou stork only in the layers that we also see the hobbits. And we don’t see them above those layers, so to me that means that they were very closely linked. They were part of one and the same ecosystem. And they even probably depended upon one another for food and competition. So I think when one went, the other went as well.
The main difference that we see between the upper layers, the Holocene layers, and the Pleistocene layers is the presence of these other large megafauna, including Homo floresiensis, two species of extinct bird– giant marabou stork and large vultures– as well, Komodo dragon, and Stegadon– which is an extinct form of elephant.
In the Homo floresiensis layers, that’s what we find. We find those taxa are always together, but then they disappear in the sequence. So what that means for Liang Bua is that life at Liang Bua wasn’t all peachy for hobbits. It was a very sometimes even dangerous place where you have to compete with large scavenging storks and vultures that are out for your food as well. So it must have been at times a very aggressive and scary place for these tiny creatures. The hobbit is this very enigmatic hominid found in Indonesia. And there’s still a lot that we don’t know about it.
So I’m hoping that through some of these more higher resolution data that we can get from the rats, we can speak to who is the hobbit. Where did they come from? What was their behaviour like? What did they eat? How did they interact with their environment? It looks like something that should be found in Africa– 3 million years old. But it’s in late Pleistocene in Indonesia. So a lot of open questions. So hopefully if we can understand a little more about their diet, then we can get to maybe who was Homo floresiensis on a larger scale.
It’s important to understand how our species has impacted the ecosystem and the environment here, particularly when we can look at it over long periods of time and understand whether or not– or maybe those species were already rare, or maybe going extinct on their own. But we can sort of see the impact that humans have had on the ecosystem here in Flores from 100,000 years ago up until the present with the deposits at Liang Bua .