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Dr. John Roach joins the Talk Show to talk about his ecological studies and then Jessi brings on Freckles the leopard gecko.

Animal Wonders:
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Hello and welcome to the SciShow Talk Show, the day on SciShow where we talk to cool people about interesting things.

This is Dr. John Roach. He is an ecologist and has been for quite a while and I just got briefed on his whole history. There is a lot to it. Start me off at the beginning of your ecology career.

JR: Well, I took a turn from studying government and doing policy and realizing that it was hard to advise people when I didn't understand science. So, when I had an opportunity to work in Yellowstone studying coyotes, I packed my bags and moved from Washington D.C. to live in Yellowstone and study coyotes.

HG: That sounds pretty awesome. Uh, when was this?

JR: Uh, this was in the mid 90's, so before wolves were introduced, when coyotes still roamed-

HG: Ruled

JR: in packs, yep. So, they had large packs there, and people were keeping track of those, and they were the premiere wildlife viewing during the winter. I used that as a stepping stone to move on to do a Master's degree. So, I took some courses getting ready for Master's, but then I started studying pikas.

Part of the reason I was interested in those is the same sorts of questions occur around pikas as did really about reintroduction of wolves.  Do pikas structure plant communities because of their fear of being eaten?

So, pikas are these rabbit like creatures. They are in the rabbit family. They are about the size of a hamster. They live in high alpine areas. They hide in rock areas because that's safe, but there is not much food there so they have to venture out from the talus to find something to eat, and the further they go, the riskier it is for them. So they tend to concentrate that foraging on areas that are near the edge of the talus. And consequently, they have a really strong and interesting impact on which plants you find where.

And this is the same idea, that people were wondering whether or not when wolves were returned either by simply reducing the number of elk or by changing where they forage, if they would change the plant communities.

HG: Mhmm

JR: They are an interesting critter from a conservation perspective because they are, uh, widely thought by some people to be a potentially "canary in the coal mine" for climate change, because as the world warms species ranges are assumed to move uphill, and if you are already on the top of the hill there is not much room to go. So there's certainly some people that are interested in pikas from that perspective, but I wasn't. I was interested in their effects on plants.

HG: So that was your Master's research...

JR: Correct.

HG: I introduced you as doctor so you must have continued.

JR: I did! So I - one of the things I like about pikas was they're charismatic and they're fun to observe. But..

HG: Ah-Adorable.

JR: Yeah! And so that was great. The difficult thing about working the high alpine is that the plants there grow really, really slowly. So we set up this experiment and we watched it for three field seasons, which is actually a fairly long Masters and small changes occurred.

During that time I had been working with some people that did aquatic work. Aquatic systems are fast. Algae grows quickly. So I moved to the desert where streams are uniquely defined and started to work on urban systems and look at how they functioned. And they were nothing like what I expected because they are artificial and they are canal water that's being moved through them, that's been pumped from underground and it's collected over long periods of time. But they are fast in terms of their ecology. Nutrients change quickly over time. Plants grow quickly and so they are really nice systems to study how ecology unfolds.

HG: So you were studying the ecology of just general water systems in the desert?

JR: Well, our lab did. Our lab was focused on that, but I had a unique opportunity. One of the things that the National Science Foundation has funded for long term— long time is something called the LTER network, Long Term Ecological Research. And the idea is that ecology unfolds over longer time scales than the typical PhD which is the average length of a study. And they have these all over the place, including Antarctica, the tall grass prairie, etc. And when I started my PhD they were starting two of the first urban ones. So there was an urban one in Phoenix and Baltimore and that afforded me the opportunity to try and understand how streams in a city might be very different than streams in the surrounding area. So we focused on this strange, artificial watershed that lay in what was historically a dry wash, where water only flowed during monsoon rains and now flowed whenever people opened a spigot.

HG: Mmm.

JR: Yeah.

HG & JR: (laugh)

JR: But it's neat. You can see these interesting ecological signals there so you can see areas that are significantly cooler just because people irrigate so much more. They're greener, they're cooler. And, they also track strange things, like income because wealthy people have the money to irrigate and manicure their lawns in a place - way that more impoverished folks don't. So you see this real difference in the climates of different neighborhoods, that is income related.

HG: Wow.

JR: So you have this weird interplay between what people do and how the ecology of the city works, and this is part of what makes these urban LTERs so interesting is trying to combine these individuals who are doing, these scientists that do social science with people like me that are more interested in ecology and link them to create a really rich understanding of how cities function.


JR: Yeah

HG:Really cool. Um...Jessi from Animal Wonders I think is now going to show us some kind of animal. So she will appear shortly. Where you're sitting and you will be scootched over one chair segment.

 Animal Wonders

HG: Hi!

JKC: Hey!

HG: Magic! It's a lizard.

JKC: Yeah! Wait.

HG: More specifically...

JKC: Yeah, yeah. Ok, this is a leopard gecko. Her name is Freckles.

HG: Freckles. God. (laughs) Of course. So this is a leopard gecko. It is, I am gonna to go ahead and say, kinda ridiculous looking.

JKC: Awww...

HG: I'm not...there is nothing...I'm not...I don't think I am going to injure its feelings.

JKC: Its sensitive.

HG: Ok. Ooh...does it like that?

JKC: Yeah! Wanna pet her?

HG: Ok, yeah. That's sorta what I expected you to feel like. I'm gonna stay in this part-

JKC: Ok! Now feel right here. Kinda like rub your fingers

HG: Oooo...whoa...that feels like - like I'm touching a bug. I would not-

JKC: A bug?!

HG: Yeah. Like a grub.

JKC: Yeah, yeah. There ya go.

HG: Yeah, it's more... more than a bug.

JKC: Yeah. Be gentle with it.

HG: OK. 

JKC: So what happen is, they store fat in that tail. It's - it's used - it's two-fold. It's used as what I like to say a refrigerator.

HG: OK, yeah.

JKC: So, it can store extra nutrients in there in the form of fat. So when it can't find food in the wild, it can just - 

HG: Just carrying around its-

JKC: Absorb it. 

HG: Lard stores.

JKC: Yeah, yeah. Which is, I think's pretty neat. But then, if a predator's gonna come along and try and eat her, she can drop her tail.

HG: I mean, you say drop, but is -is it - it's more like it gets yanked off.

JKC: Um, they can actually - it can get yanked off. But she can actually let go of it without without any pressure coming onto it. Yeah. Yeah. 

HG: That's crazy.

JKC: Um, yeah. So, she's gets really, really scared, you know, she'll make this movement and it'll break off. And actually the tailbone there actually has little fractures on it so it comes off easier-

HG: And then that's a one time thing.

JKC: Uh-uhn.

HG: Wow.

JKC: Yeah! OK, so this is really cool. So this will actually like -

JKC & HG: (laugh)

HG: Animals are weird!

JKC: They're awesome! So, the tail will like twitch for up to 30 minutes.

HG: Right. 

JKC: So, it's gonna like move around.

HG: Right, so it'll be a 'lil delicious.

JKC: Exactly. A delicious morsel sitting there with no defenses. And so the predator will come and will chomp on that, and be very satisfied - it's delicious - and, and very nutritious, and uh. The gecko will run away, which can run much faster without this heavy tail on it too. So it will escape with its life. And then, it can actually start to regenerate its tail. As long as she gets food-

HG: Right. 

JKC: whenever she needs, and actually extra food because now she's not just sustaining her normal function, she has to regrow her tail. When you think of a gecko, what do you - where do you picture them?

HG: In Geico advertisements.

JKC: Yeah.

HG: Sorry.

JKC: Yeah.

HG: This is - this is not my fault.

JKC: I know! I know. It's alright. At least you know what a gecko is, because that -

HG: Yeah, uh, jungle-y.

JKC: Mhmm.

HG: Moist.

JKC: Are they crawling on the ground, or are they stuck somewhere?

HG: Oh, yeah, stuck somewhere.

JKC: Yeah. Stuck up somewhere, ya know. Because they have those really cool hairs on - on their feet that allow them to do that.
These guys don't. Ya know, if I stuck her on a smooth surface, she'd fall right off, just like we would. She has little claws on there. Can you imagine having those pads that stick to things?

HG: Oh yeah, sand all on your sticky pads. 

JKC: Would be terrible, terrible. Would you like to hold her? 

HG: Of course!

JKC: Yes.

HG: Uh, insectivore.

JKC: And she just walks, so just - just keep putting your hands in front of her. Yeah. Um, well she's a, yup, carnivore - 

HG: Yeah.

JKC: And so she's only going to consume insects. And sometimes, little tiny baby mice. But mostly, it's going to be crickets and worms and other little grubs like that. 

HG: Where ya going? 

JKC: When they're babies, they hatch out of an egg, and - she's truckin'! Careful. She will fall off your arm. So when they're babies, they're born. They come out and they have these black stripes on them. They look super cute.

HG: Cute.

JKC: You'll find them in pet stores, and people will get 'em. And you have to do your research, because I've seen way too many cases where they're given to small children as first time pets. And, small children, "oh! I want to pick up the little oh, it ran away from me. Oh, I'll just grab its tail and pick it up."

HG: Oh, yeah. 

JKC: And the tail come off. Which is very stressful to the lizard, it's not a good thing. Just because they can regenerate it, doesn't mean that you should make them. 

HG: Beautiful animal. Where you going?

JKC: See if she wants to eat something.

HG: Oh yeah, we got food for you.

JKC: Just set her on the table.

HG: I see it. Do you see it?

JKC: I love when they hunt.

HG: Get it. Get it. 

JKC: Wait, move your hand. Oh, oh, oh. Let's see if she is - oh she sees it! Ok, watch her tail. If she does it do though.

HG: What is it? Oh, oh. You look like a cat.

JKC: Ohhhh!

HG:Oh man, this thing has no idea what it - what it's in for. It was walking toward it.

JKC: Delicious. Well, she didn't do it. Maybe she's a little too fat. Her tail's pretty heavy right now. But a lot of times, they'll do that prowl thing. And then, right before they launch towards it, the tail will like do this little twitch -

HG: Twitch

JKC: Like cats do. Very similar to cats. It's really neat.

HG: It definitely looked like a cat. Yeah, yummy. That was good.

JKC: Oh, you did so good. Would you like to hold her?

JR: Sure.

HG: We're so lucky.

JR: Very. This thing's very content.

HG: Yeah. 

JKC: Yeah.

JR: Well fed.

JKC & HG: (laugh)

JKC: Happy.

HG: Yes. Your, your leopard geckos have the biggest tails Jessi.

JKC: Oh, thank you. (laughs) Yeah. Here. I'll put her up so you can talk to her.

HG: Yeah. Thanks for your visit. Have a good day and enjoy your worm things. Appreciate sharing your peculiarity with us. Thanks for coming, Jessi. Jessi is, there's a link to her youtube channel in the description, which you can check out. And thank you to Dr. John Roach for sharing your story and insights with us as well.

JR: Thank you for having me.

HG: Thank you for watching. If you want to keep getting smarter with us, you can go to and subscribe.

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