Koala Bears and Eucalyptus - Periodic Table of Videos

I'm in Cleland Wildlife Park in Adelaide sudden Australia and I'm feeding a kangaroo been a minute I'm going to see the Koala and I'm really excited because koalas eat eucalyptus and eucalyptus has been really important in the development of Australian chemistry two days ago I was giving a lecture and I made a terrible mistake I said I was going to see a koala bear because that's what we call them in England and I was told off at once they're koalas they're not bears so I apologized eucalyptus is a whole series of different trees in the same family that grow in Australia and this is one of them here they're nearly I think seven or eight hundred different species but what characterizes most of them is that if you break off a leaf and crunch it up you get a very strange smell from the oil and it was analyzing this oil which was really one of the starts of chemistry in Australia boy I'm just trying to find it there that's a nicely good boy you can extract quite a lot of oil out of this leaves and the oil is quite poisonous so very few animals eat the leaves of these trees which means that they're here for the koalas because the koalas have a digestive system that will get rid of the poisons which would kill other animals so the tree in a way is like special restaurants for the koalas and nobody else can eat them analyzing the oil was quite a challenge and some of the first chemists isolated a molecule that's called eucalyptol or sometimes it has a more technical name of 1/8 Cine old so while I was here in Australia I found an article in this magazine about the first chemist in Australia and very conveniently for me it has a nice picture of these molecules and this molecule here has a variety properties but the oil itself is an insecticide it has a nasty smell and presumably the insects don't like it either my father used to use eucalyptus oil when he had a cold and one day and I don't know why he put it on his hair by mistake and my god there was a smell could hardly sit in the car with him so I'm sure the insects don't like it either and even to this day you can get eucalyptus oil to buy as a remedy for yourself here is photos of old eucalyptus oil but in the shop here at the Wildlife Center we've saw seen eucalyptus hand cream eucalyptus soap even eucalyptus tea I don't know perhaps you can drink and keep the insects away I don't know I'm on across his back just put one hand across his back his hand across his back beautiful eucalyptus oil is a mixture of compounds but the sin oil is the major component and depending on the species of eucalyptus tree so you get more or less and in some species it's really quite a high percentage of the oil and that's the ones that they found where they found it first but now they've found it in all sorts of them there are those types of eucalyptus tree which grow in Western Australia near the city of Perth where the tree has lots of different stems which they think the the wood from those trees could perhaps be used as a biofuel for aeroplanes and the company now is trying to make aviation fuel out of eucalyptus trees but I think I wouldn't wait to go home till they've perfected the process but let's come back to the coal the Bears because the sorry let's try that again let's come back to the koalas and the koalas eat the leaves but they're very fussy they only want some leaves and not others and chemists have done quite a lot of work to try and decide why they choose this leaf and not another one and the answer seems to be that they sense the amount of a toxic compound or a series of toxic compounds that are based on the benzene compound called fluoro glucan all its fluoro with a pH so it's not got fluorine in it and this is try hydroxybenzene and this in itself is rather an interesting compound because the industrial manufacture florida Lucan all goes via TNT the explosive and you can see these trees are making Florida Lucca Knoll and they're not explosive so they must be using a different pathway and in fact what they do is that they make the compound via a ring of six carbon atoms without the benzene character and then right at the end they convert this into the benzene whereas industrial chemists begin with benzene and work the other way so there's a lot of clever chemistry that we can learn from trees in the tree there's no florid glucan on itself but compounds made from it and the tree I think has it to discourage animals from eating it and even the Koala doesn't like it so it goes for those leaves where the flora glucan all levels are low and I expect that the koalas have evolved so that they can smell this compound in low levels so that even if we couldn't smell it they could tell that there wasn't much flora gluten or what did you think I thought holding the was fantastic I think it will be probably the best part of my whole trip though I'm still going to see some bolognese but these leaves that the koalas eat don't have much nutritional value part of the reason they eat it is to get water because normally unless they're ill they don't drink water at all but they have to eat really quite a lot the one I was holding has to eat nearly a kilo of leaves a day so and takes quite a long time so all the koala but so all the koala does is to sleep and eat and eat and sleep with about 19 hours of sleep and five hours of eating so it sounds quite a good life no time to make chemistry videos if you're a Karla Baehr except the one we saw you just call it koala bear again [Laughter]

Channel: Periodic Videos

Views: 361,120

Rating: 4.9744987 out of 5

Keywords: eucalyptus, oil, trees, koalas

Id: FmU_SGdtHE0

Length: 8min 16sec (496 seconds)

Published: Tue Sep 27 2011