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Like many kids, I dissected owl pellets when I was in school - but I never realized they can be used by scientists to learn about certain aspects of an ecosystem. And today, paleontologists like Matt McDowell are using these pellets to learn about the history of an environment, to preserve them for the future.
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Natural News from The Field Museum, our new news show!:

"Looking forward to the past: what fossils tell us about extinction,"

"Extinction means more than a loss of species to Australia's delicate ecosystems"

To learn more about Matt's work and research:

You can (and should!) read Matt's papers, which we referenced for this episode:

Matthew McDowell's research is being supported by The Field Museum, and a grant from the Australia Awards -- Endeavour Scholarships and Fellowships. For more information, visit their website:


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What if I told you that this 10,000-year-old owl pellet can hold crucial information for preserving the future of Australia's fragile ecosystems?

It's true. The specimen along with a 100,000 others was collected by Field curator Bill Turnbull from the Nullarbor plain region of southern Australia in the 1950s.

And today, its information is being used to help perserve Australian habitats. Here's the neat thing about this congealed bird vomit. Nocturnal raptors like owls primarily feed on rodents and they eat a lot to satisfy their dietary needs.

The bones and fur aren't digested so those parts are regurgitated in the form of pellets. Some owl species return to the same roosting sites for generations regurgitating pellets in massive piles over a period of many years and luckily for us, a few of these sites have been preserved in caves and sheltered from the elements. So in the last tens to hundreds of thousands of years, these large owl pellet accumulations have given paleontologists a phenomenal record for what sort of rodents were historically found in the region.

And just like how fossil life is stratified in layers of rock, the ages of rodents too become stratified the deeper you dig in these massive piles of raptor pellets. So, why are so interested in this information? Well, in the last 200 years since European settlement in Australia, the country has experienced an alarming rate of mammal extinction.

Greated than any other continent. Since there's no written record of what the mammal diversity of Australia looked like before Europeans arrived, scientists have to be creative with interpreting the country's plant and animal history, which in this case means sorting through these raptor pellets as a great starting point. This gives scientists a way to look at the past in order to help shape the future.

And I've got a ton of questions about this, so recently we sat down with Dr. Matthew McDowell, a post-doctoral researcher at Flinders University in South Australia to learn more about his work as a paleoecologist and his affection for raptor pallets. [Dr. Mc

Dowell:] This is a sample of the kind of thing that gets scooped up off of the floor of a cave with the fine dust gotten rid of. [

Emily:] Okay. [Dr. Mc

Dowell:] Now, that's usually made up of things like this – an owl has eaten and then regurgitated before it flies out to go hunting the next night. We don't have any of the really fresh ones but they're all very glossy and mucus-covered, and... Yeah. May be gross, but... [

Emily:] Kind of fun stuff. [Dr. Mc

Dowell:] Yeah. This has been washed pretty well except for these chunks on top which have been kept so that you can see what it looked like. [

Emily:] And then, when you have all of this material, you're taking a pile like this and you're having to sort through all of it to figure out the species under there. [Dr. Mc

Dowell:] Yeah. That's best done with the teeth. For a couple of reasons. They're the most durable part of an animal's body, so they last the longest.

But they're also complex shapes because different food is best processed by different types of teeth. And then you get to the stage here where you've only got the bits that are easily identified which are mainly teeth and jaws. Once we go from these, we identify them, we work out whether it's the left or the right specimen, what kind of species it is, then it goes to this stage where it gets put in a vial with a label. [

Emily:] With its own number. [Dr. Mc

Dowell:] Yeah, with its own number. Individually, usually individually, sometimes in a lot if you've got millions of them like we do in this case. And that one's got all of its teeth. So that would be an easy one to identify. [

Emily:] What is it? [Dr. Mc

Dowell:] I don't know, I haven't got a microscope. [

Emily:] Oh. [

Emily:] So, through the process of what seems like a really gross thing, which is sorting through owl vomit, you're able to look at what sort of rodents and small animals used to be living in an area. [Dr. Mc

Dowell:] Yeah. [

Emily:] That's amazing. [Dr. Mc

Dowell:] The longest continuous history that I've done this for is on Kangaroo Island and it's continuously collecting owl pellets for 150,000 years. [

Emily:] Are you serious? [Dr. Mc

Dowell:] Yeah, just piled on top of each other all the way through time. [

Emily:] So how has this information that you've learned about all of the species and diversity of these caves from relatively long time ago – how has that changed in the last 200 years since Europeans have been in Australia? Dr. Mc

Dowell:] Oh, that's a great question. Europeans in Australia were, I think justifiably, more interested in feeding their family by clearing a heap of land and planting wheat than they were in what little animals used to live there. You can learn just how much damage we did to the environment by comparing fossils that are maybe only 300 or 400 years old to what should be living in the area today. My opinion is that those young fossils are a much better indicator of what should be living in a park or a place today, than the animals that are living there right now. [

Emily:] Ultimately, what do you do with this information, now that you know what is in a particular cave or a region? [Dr. Mc

Dowell:] Well, we can use it to work out a number of different things. From very young fossils we can work out what should be in the national parks, typically in Australia there will be three or four native mammals in a national park, but if you look at the fossil record, there's 20 to 25 native mammals that should be there. We can also use it to look at how climates have changed through time and then we can take that information that we've learned from conditions in the past being represented by different animals, and we can then make predictive models to ask ourselves, 'Well, if the climate conditions were like this, what animal would be expected to live in the area in the future?' And that is in terms of conservation management really important. You know, we can spend a million dollars on a park and make it beautiful and find that's it's only actually useful for a hundred years.

If I'm doing conservation, I think we should get at least a thousand years out of our million bucks. [

Emily:] What kind of challenges have you run into when trying to advocate for rodents? Because they're not exactly the most, uh, charismatic species... I mean people can get behind saving pandas and tigers, but when you tell them that there's a rare rat living in an area, how do they respond? [Dr. Mc

Dowell:] Yeah, so it is difficult to champion a rodent, but it's really easy to sell climate change. These little animals live for only a couple of years, so they're very sensitive to their environment. And they move with the climate and sort of habitat envelope, by that I mean, you know, if you've got an overlayer of the right kind of plants, and the right temperature, the right kind of soil, all of those factors play into where an animal will live, and as climate changes, they move. They also do things that help the community to be supported, so some might cache seeds and forget where they buried them so some of those seeds will germinate and grow into plants that had the best possible start, because that will put them to moist fluffy ground because it's been dug up.

Some might shift fungal spores around, which help other plants... Fungus often grows on plant roots and it's much better at collecting water than tree roots are. So without a lot of these animals that dig, you lose a lot of that functionality, you know, in a community, and all of the ecology is damaged by that.

And it makes it less stable, more easily broken by climate change. And also, it means that if you want to keep it, you have to spend more money. So, much better to start with something that's good and well supported, and, you know, put a little bit of money into it and keep it ticking over than to go, 'Oh no, we've only got 13 more northern hairy-nosed wombats left, we have to throw millions of dollars at it to make sure it doesn't go extinct.' [

Emily:] 'Oh noo!' It's kinda late at that point. [Dr. Mc

Dowell:] Yeah. [

Emily:] So this cave deposit material, is this primarily unique to Australia, or is there a chance that there would be stuff like this found in any country? [Dr. Mc

Dowell:] That's a really good question. The animals in different countries change but very much the processes stay the same. Anywhere you've got cave-dwelling birds of prey, the barn owl particularly lives in every continent of the world except Antarctica, so nearly everyone's got one, the animals that they're capable of killing quickly and in every continent, they're piling them in caves for us. [

Emily:] So there's probably a cave near you. [Dr. Mc

Dowell:] Yeah. Quite right. [

Emily:] Full of raptor pellets. Just for the pickin'.