 Right, so what I'm going to do in this talk is I'm first of all going to give you a bit of background to variation in aging rates which leads to variation in lifespan and I'll tell you first a bit about that in general and then I'm going to tell you how remarkable birds are and then I'm going to talk to you a bit about work that I do I work on many aspects related to aging I'm going to tell you a bit about stress and telomere loss and don't worry I'm sure you know what stress is but you might not know what telomere loss is now when we think about what shapes how animals live their lives all organisms have finite resources that are available to them from their environment and evolution has shaped different species to use those resources in different ways so that they get the highest reproductive success so they can use the resources for growth they can use the resources for reproduction and they can use the resources for self maintenance different organisms partition their resources in different ways and what that means is we see a huge variety in the biodiversity of animal life history some animals put a lot of resources into growth some stay small and put more resources into reproduction some just do one big bang reproduction others take it slowly and they reproduce maybe every year maybe not even every year and then some organisms put a lot of resource into self maintenance and it's the amount of resource that goes into self maintenance that is important when we think about aging so most organisms have maximum life span and that's due to variation in the rate in which bodies deteriorate we all deteriorate some of us faster than others unfortunately we don't all do self portraits of ourselves as we age so what you can see here are Rembrandt's self portraits when he was young and then go older and then a bit older and older again and you can see that he charted the changes in himself different species age at different rates and that's a really interesting area of biology now why does aging take place? It takes place because you get an accumulation of damage with time damage to the DNA that we all rely on to make our bodies work our DNA is being transcribed all the time in order to to give us the physiology the cell turnover the cognitive power that we need and DNA gets damaged with time and the rate at which that damage occurs determines how quickly we age so damage to ourselves and our DNA increases with age and causes some malfunction now the other thing that also causes us damage is that we use oxygen to generate energy and producing energy from oxygen a byproduct is the generation of chemicals that cause oxidative damage okay what are called free radicals you're probably always being told that certain vitamins will help because they are antioxidants in other words they might slow down the oxidative damage that our bodies are generating all the time what's really happening is we're rusting so in the same way that your car gets oxidized or many other things your body to an extent you might say I'm a bit rusty but literally you probably are now of course organisms evolve ways of trying to combat that damage they have antioxidant defenses many of the what as I said I want to go many of the the vitamins that we rely on are antioxidants you know you you're always being so creams that you can put on your face that are with a vitamin E that is an antioxidant there are lots and lots of these antioxidants different animals and other organisms use them in different ways so there are antioxidant processes to combat that takes up resources and there are also repair mechanisms we can repair our damaged DNA we can repair our damaged cells our cells are turning over all the time and and as you know some organisms they can regenerate whole parts of their body they can grow again we don't do that so a lot to do with how much of your energy evolution has shaped you to put into repair so the damage will accumulate at different rates in different organisms and you can see that so here's some pictures of my husband Neil now Neil stranded in France because the whole of France is on strike so he's not here for you to compare this but this is Neil when he was a young man he's a bit older now which is roughly how he looked when I met him then he became a bit more sort of scrubby looking there he's trying to look a bit hip I would say and not entirely succeeding and here he is a recent photograph now and you can see that he's changed quite a lot he's he's lost actually lost more of his hair than shown in that picture and his hair is going gray his skin looks a bit different but one thing I just for the men in the audience I'd like to tell you is that the degree of baldness has no relationship with lifespan if you go bald early or late doesn't affect how long you're going to live if your hair goes gray that's also not related to lifespan so there are changes that take place with age that are not predictive of how long you're going to live they might give some people a clue on how old you are but they might not so we see these changes and some of them we just can't repair so some organisms live much longer than others so here's some examples this is an ocean clam a bivalve that can eat the record lifespan in this species is 592 years another amazing animal is the green and shark 392 years one of the most amazing organisms is a plant the bristle corn pine which is reckoned to live over 5000 years now when it comes to plants I'm not going to talk about plants their biology is very different and it starts to become difficult to say whether or not it's the same organism there's so much change going here's another little animal that you find in ponds called hydro and it starts to show almost negligible aging but again its biology is very different another remarkable thing are what you see in some of the social insects like ants or bees where you have a queen as you see here here's a queen ant she's bigger than the worker ants here the the workers around here the queen ant can live 28 years in some species and the workers only two to three weeks they have the same genome and it's not simply explained by the workers working harder their genome is being transcribed differently and that makes a big change to how quickly they age these workers even if you give them an easy time their lifespan will be short so big differences in biology they are even with the same genetics so I'm going to run through now a few things that broadly speaking relate to animal lifespans okay so body size is one as I'm sure you know larger animals tend to live longer and here's a plot here on this axis here is body mass so small body mass large body mass short lifespan long lifespan these are logarithmic plots and then you get a straight line you can see that the big animals tend to have longer lifespans that's a broad pattern but you can also see that there's a lot of scatter around that but generally speaking large species have longer lives than small species but this size related difference in lifespan it's not always like that if you think of dogs now now we're looking within a species we breed dogs to be different sizes uh so you can have a great day way up here this is male body mass big dog and I don't really know what that is but it's a little dog looks bigger than it really is so it's a little dog anybody who's owned a jack russell will know that jack russells live a long time anybody who's owned a great day nor us and bernard or a pyrenean mountain dog will know that these dogs have a short lifespan maybe seven years your great jack russell might last 20 years so within species like this we don't see that same pattern we see that the bigger ones have shorter lives they're aging faster so growth rate matters then in in this case because what these big dogs do is they grow fast most evolved large animals grow slowly when we tinker with the biology of these dogs we get them big by making them grow fast and faster growth is linked to shorter lifespan okay so that's why we see that kind of pattern in the dogs they're growing too fast another thing that influences animal lifespan is body temperature animals that are cold-blooded which are is the majority of animals tend to live much longer than warm-blooded animals the war there are only two broad taxa that are warm-blooded the mammals that's the hairy ones animals with hair or in some cases less hair as they get older are the warm-blooded mammals and then we have the birds and they're also warm-blooded cold-blooded animals of the same size as a warm-blooded animal usually live much longer so here's a giant tortoise and they live certainly upwards of or can live upwards of 150 years this is an Aldabra tortoise I think there's one called Jonathan that's reckoned to be 192 you can can't always be sure of course Jonathan can't really tell us but this giant tortoise its body mass is similar to that of a lion and the maximum lifespan of a lion is about 25 years though body temperature then also has an impact on lifespan broadly speaking the other thing of course is the rate of living the metabolic rate how fast animals are using up energy how quickly their bodies are go are sort of how fast you're living if you like higher here again is one of these plots we've got metabolic rate resting metabolic rate on this axis again it's a logged axis log lifespan you can see that a low metabolic rate this is just for the mammals those with low metabolic rates of longer lifespan sorry those with low metabolic rates of longer lifespan short metabolic rates sorry I'm getting muddled here fast metabolic high metabolic rate short lifespan right so the rate of living is related to lifespan high metabolism short life low metabolism long life so I've told you four things then that broadly speaking are associated with aging slowly that's small size sorry it's body size and small size gives you longer life fast growth shortens life having a warm body seems to shorten life and and having a high metabolic rate also seems to be associated with a shorter life now what about the birds then where do they come in I said a small body is associated then tends to be associated with a shorter life do birds have small bodies yes birds have to fly and they keep their body small evolution has shaped them that way do birds grow fast yes birds grow really fast they tend to be seasonal breeders as you know they're growing while they're in the nest and most birds are fully grown by the time they leave the nest they do very little growth after that because they've got to fly and they've got to get ready for flight and so they get most of their growth done while they're still in the nest so they're growing fast do they have a warm body even for an end of the hour they have a warm body even for a warm-blooded animal our time our body temperatures around about 37 38 maybe if it goes above 40 we are in real trouble the birds normal most birds their normal running temperature is 42 degrees so their bodies are warm and their metabolic rates are also very high so here's two animals then a great tit a bird and a wood mouse a mama both warm-blooded both around about the same body mass anybody want to hazard the guess as to what the maximum lifespan of a great tit you probably see it in your garden talking maximal lifespan here not average lifespan but maximal three years a wood mouse anybody know wood mice okay the the sort of rough lifespan of a maximal lifespan of a great tit if it doesn't get eaten or die of salvation or something else is about 14 years now it's a very small bird but a wood mouse also if it's protected its maximum lifespan is about 20 months here's two more that are about the same size a night a duck and a rabbit the lifespan of a night a duck 36 years this is in the wild some occasionally a little bit longer than that but that's roughly 36 is about a maximal lifespan we know a lot about birds and their lifespan in the wild because you can put rings on birds there's a whole army of keen bird ringers who ring birds in the early days they were the rings were made of aluminium and we thought birds live not as long as they do once staying the steel bird rings came in with individual identification on them it became clear that birds live a lot longer than we thought they did so I did up then about 36 years a rabbit uh its maximum lifespan is around about nine years and that's that's pushy for a rabbit so contrary to what I told you then about the life history traits of birds their warm bodies their small size their fast growth their fast metabolism all of which would lead us to expect a short life birds have long lives just to show you are not that in another way here's a picture of a biologist who used to work at Aberdeen University a man called George Dunnett who did some wonderful work uh with this bird species here the full one one of our seabirds in scotland green song cliffs George worked in Orkney and and when he was a young man he caught this homework and he put a ring on its leg a stainless steel ring luckily and he came back 30 years later and he caught the same bird again and he knew it was the same bird because it still had its ring on and that bird was still at its nest site still greeting had a had an egg uh in its nest and it didn't look any different to George now as you can see George looked a bit different and I don't think he was can't be sure I'm not sure if he was reproductively active uh at that time um but anyway we know for sure that the fuma was so on average birds live three times as long as a mammal of the same body size that's on average some much longer there are some groups of birds that are exceptionally long live the seabirds tend to live for a very long time they reproduce very slowly they although they grow fast they delay their maturation that those fuma I showed you that they don't start breeding till they're nine about nine years old parrots if anybody's kept a parrot have you got a parrot when you're a child it's likely it might still be with you parrots are really long lived they can live 80 90 years and don't get any now or they're in trouble um sorry that that was a bit insulting um this is one of our uh a very small seabird that storm petal leachy storm petal only weighs 35 grams these birds are living in a hostile environment the marine environment uh leachy storm petal can reach 38 years or more I don't know that's me making that noise or so why do birds have such a long life why do they age so slowly well one of the reasons is that flying is very demanding lifestyle um you have to keep a low body mass uh in order to get off the ground you have to keep the body in very good condition in order to fly you can't fly with a zimmer frame let's say so and the takeoff especially is very expensive uh some birds you know can glide they don't always have to use flapping flight but evolution has favored then going back to what I showed you at the beginning animals have to allocate their resources birds allocate a lot of resources to maintaining their body because if they don't they won't be able to fly so high priority uh for flight also because they can fly they've escaped uh many of the causes of death they can avoid a lot of predators they can migrate away from an area when conditions get rough it can of course migrate very long distances think of the arctic turn a very small bird and it will fly from the arctic to the Antarctic in winter and back again in the summer the distance it covers is phenomenal i used to work with arctic turns uh they can live uh 25 years more long live but energetically uh they do a lot so here's a plot here that's quite a lot on it but what i just want to show you in this plot so again these are these log plots this is lifespan on this axis and body mass the blue dots are birds uh and and some flying mammals there are some mammals that say fly but you know they get flying squirrels uh and so on and you also get bats um and then you have the non-flying mammals and the non-flying birds you know there are birds like emus and so on um but what i want you to see is that the relationship between body mass and lifespan is different if you're a flying animal flying animals whether they be birds or mammals have long lives bats are another group that are small and live long uh so the lifespan of flying animals tend to be long for the kind of reasons uh that i've just been telling you so flight then you've got to be in good condition it's energetically demanding another thing that birds do is i said that when we're producing energy from oxygen birds produce less of these damaging free radicals when generating energy for a unit of production of energy the bird is generating less damaging free radicals than a mammal is so they they're doing thing they're doing the same thing uh they're producing energy from oxygen but they're doing it in a slightly different way that's less damaging even though they need a lot of energy and other things about birds is that their body cells people have cultured body cells from birds and mammals and subjected to cells to different kinds of toxins different kind of stressors and the bird's body cells are more resistant even in cell culture they're more stress resistant so they're involved mechanisms uh to help them keep their body in good shape also because bird bodies are small they're not doing as much cell division as we are and i'll come back to to why that's uh important so the birds have evolved some tricks uh that help them uh to live longer and age more slowly now i'm not suggesting that uh you fly between the arctic and the Antarctic or even that you start learning to fly because these are evolved responses uh it's too late for us the the animals that evolved those kind of things are the birds but there are probably things we can learn from the birds about how to manage uh damage so i'm now going to tell you a little bit uh about some of the kind of research uh that i've been doing recently and before i do that i just want to say that when you do research i'm i'm talking about research done in my group it's always a team effort there are a large number of people involved uh some of them might be students phd students uh postdoctoral researchers colleagues sometimes they're working in harsh harsh conditions sometimes in sometimes in difficult occasions um and and together uh we've done a lot of interesting things and i'm only going to tell you a very few of those because i don't have time uh to tell you a lot now within my group we've worked on lots of different kinds of birds we've done work on many sea birds uh the guillemots here the different kinds of gulls less a black black gull herring gull cutiwake churns here we've also worked with storm petros black guillemots starlings a little bit of work with uh lab work with uh not with albatrosses but not the albatross itself with with blood samples storm them with giant petros and so on with starlings shags but two species in particular i'm going to show you some information from one is this bird uh which uh i've been involved in a long-term study of this species on the island of isla uh it's the red bill chuff chuff is a member of the cruel family very smart birds as you know uh black bird it has red bill red legs this is the red bill chuff you might have seen it uh on isla we only have it on island call and say and there's another side to the work that we do there that's related to the conservation uh of this species there's also the alpine chuff which you might see uh when you're on a holiday in the continent very similar uh but it has yellow legs uh and a yellow bill i'm going to show you some data on a little bit of information on chuffs uh and then on this bird the zebra finch uh which we work with in captivity um the zebra finch is in captivity we're not uh um the zebra finch is a common little pet bird you can buy it in pet shops very easy uh to keep and breed in captivity um and uh and that's why we use it so this is some chuffs at an s site on isla they breed uh in buildings as well as on cliffs we've been studying these birds since 1981 and we have a lot of data on aspects relating to their aging and birds do age in the wild so i'm just going to show you a couple of graphs here this is different age classes of chuffs here one year old two year olds up to uh over 13 years old and this is their mortality rate their probability of survival um it gets the probability of survival goes up on average uh as is the case with many animals they're more at risk when they're young don't quite know what they're doing they're most susceptible to predators and so on and then as they start to show signs of aging they're again more susceptible to predators and other aspects of their body function starts to fail so we see that kind of bell shaped curve in the chuff and the sort of maximum lifespan of the chuff is about 15 years so we see that survival change with age this is uh their breeding performance this is their clutch size and and it's corrected here don't worry about the actual figures it's corrected for year effects because sometimes it's a good year sometimes it's a bad year this is their sort of standardized clutch size and this is their age uh of the female you can see when females are young they have a small clutch size and when they're old they have a small clutch size again now some of that change is not due to aging because some birds have died right and it turns out say that in these chuffs we know that some of the birds who are laying small clutch sizes when they're old always laid small clutch sizes and they just live longer right so they're putting less effort into reproduction and they live longer um so we can't you can't just look at these graphs and in fair aging but in this species we've also followed individuals uh and we know that individual performance declines with age so from these kind of long term studies in the field we can show uh that aging does take place in the natural environment in birds people used to say it didn't uh that birds didn't long live long enough to age uh some of that was because the rings had fallen off as I said earlier um so another thing just as an aside uh I don't have time to talk about it one of the things uh about birds is they continue reproducing the females will continue reproducing for all of their life and that's a typical pattern in most animals our own species is different as you know women are unable to reproduce when they're only a little more than well certainly uh just about 60 percent through their lives they've still got a lot of that adult life to come and yet they're still reproducing so that is something uh is also a great biological interest but I'm not going to talk anymore about it um what we've been uh one of our focuses in particular is on uh responses to stress how that influences aging rate we're looking at any energy generation uh again on how that relates to aging rate so I'm going to tell you just about two things uh I'm going to tell you about the effects of early life stress exposure on lifespan and then I'm going to come back to something I mentioned earlier which was this telomere loss now we work with these zebra finches in captivity uh we're able to follow individuals throughout their lives and they change uh this is a chick it's a bit scoffy looking it's still in the nest it's but it's almost finished growing this is an adolescent these are males uh it acquires it's nice plumage uh which is going to attract females or not and and then by the time it's an adult it's lost all this darkness on the bill it's got a nice stripe there uh it might have you can't see it in this one it'll have nice speckles on it and a nice blood band on its chest and that really turns on uh females in this species um when they get old they don't look quite so good uh they start to look scruffy much bit rusty just like we do but it does mean you can follow through individuals now uh in general stress exposure is known to have long term consequences for health and longevity but the outcome of that stress exposure will vary uh according to the life stage more serious in the young animal uh it varies with species small larger animals and it varies with how severe the stress is stress is not always bad but severe stress or quite a lot of stress in early life is bad and I'll show you an example of that in a moment there's a kind of optimal level uh of stress that's good for you maybe that's why in private schools uh you get it rough compared you know well actually I'm going down a tunnel there I'll come back from it um let's say there's an optimal level of stress um now one of the things one of the kind of uh studies that we did was to increase stress exposure increase the stress hormone levels of zebra finches uh in early life not not to a great degree just to the extent that might occur if they if they were seeing a predator maybe twice a day um then that's a bit stressful so that happened only when they were nestlings okay only in the first uh two to three weeks of life and this is what happened to their survival so the black ones are the control group very little stress the red ones are the ones that got some early life stress the treatment the early life treatment there's no difference throughout uh almost the first year of life in survival in fact there's very little difference up until they start to grow old right these zebra finches are beginning to grow old and then you see that the ones who had early life stress the average lifespan is much shorter the growing old faster uh as a consequence of that early life stress so stress in early life is not good news one thing about these individuals who've had a more stressful early life is they're much more stress reactive and they will be like that all of their life when they encounter stress they're much more reactive now that might be helpful it might be that in the natural environment a signal in early life that the environment is a bit more dangerous is a good thing then you adjust your sort of stress responses so you react quickly then you won't get eaten so quickly by a predator you won't be so laid back but that carries costs which is accelerated aging another interesting thing that we found in these experiments paired the birds up was that when you pair a bird that hasn't had stress was one that has had stress remember a long time ago in their early life you or when I say you the partner catches the stress almost like a disease the partner's life will also be shorter in the same way that the individual that had early life stress so that having a breeding partner in the case of these birds that experienced early life stress has an adverse effect on lifespan and we've been looking at that subsequently in a bit more detail what take home message might you take from that choose your partner carefully maybe have a look at the in-laws and see whether you think they might have stressed your potential partner in early life in which case run away now this brings me to telomeres okay and this is a complex bit of what I was going to tell you a little bit about it we work a lot with what are called telomeres so what are telomeres on animals or or all the what we call the eukaryotic animals the non-bacteria and so on who have cells in their body with a nucleus inside that nucleus is the DNA and that DNA is it on chromosomes it's split up into chromosomes unlike bacteria of DNA which is a circular loop so we got these linear chromosomes there are lots of advantages to having these linear chromosomes I don't have time to go into that but it does mean that these chromosomes have ends and the sound needs to know that these are true ends and not a bit of broken chromosome right otherwise the repair mechanisms might start joining chromosomes together so you have these structures at the ends of the chromosomes that are special bits of DNA that mark the chromosome end right so if you think of a shoelace right then you have little protective things at the end of your shoelace but when cells divide these little specialized bits of DNA they don't code for anything they're just protected they get shorter like the ends of your shoelace start to free the reason why telomeres get shorter is to do with how we replicate DNA during cell division I won't go into that they just they get shorter the more of the cells divide the shorter the telomeres get so they get worn away each time cells divide and then they might malfunction which will cause this kind of instability in the cell so what usually happens then is once that's happened the cell will die it's no longer its telomeres aren't functioning and there are special mechanisms that kill these cells or make them die they don't function anymore and they're they're out of the picture so this shortening the more cells have been dividing telomere shortening is what is referred to as one of the hallmarks of aging one of the processes responsible for deterioration telomeres that aren't functioning there's more dysfunction with age right obviously as you've grown older yourselves even your kind of pool of cells or called the stem cells they're beginning to get bit worn also and telomere dysfunction has very serious consequences usually for health in later life but if it happens early in life that's also very bad it's linked to cancer it's linked to cardiovascular disease it's linked to poor cognitive and immune function linked to toxin resilience linked to arthritis and many of the kinds of diseases we think of as degenerative diseases age related telomere erosion is part of that we see variation in the loss rate amongst individuals of the same species and that's linked to lifespan and in some animals and some tissues telomere there are enzymes which can restore telomere length now here's the you know changes in telomere lengths in the zebra finch with age up to seven years old here this was a group of zebra finches where we can measure telomere length from tiny blood samples and you can see the decline it's pretty fast in early life not quite so steep later in life but it is going down and we see that in humans also we see that in many many animals not all that telomere length declines with age and the dynamics of that are very interesting now it turns out that stress exposure in early life accelerates telomere loss so that's one of the reasons that's underlying that shortening of the lifespan I showed you in the zebra finch as they get old interestingly in the zebra finch mild stress in adulthood can actually reduce telomere loss and reduce mortality risk in middle age right so what it seems to do is exposure to a little bit of stress is actually beneficial at that life stage in those circumstances but only only in middle age it's only delaying aging it doesn't necessarily extend lifespan all that much but it's still evidence of a beneficial effect and we see that both maternal and paternal age in the in the zebra finch can influence telomere length in their offspring older age birds mother or father influence offspring telomere length not just in the zebra finch and in other species so I'm going to leave you with one positive note for the men at least I said it's generally the case in most animals studied so far the older fathers have offspring with shorter telomeres as is the case with older mothers very very interestingly in humans that's not the case old fathers have offspring with longer telomere and it's been shown that the telomeres in the spare of older men have longer telomeres and that's a bit of a puzzle as to why that should be so that's not to say there aren't other lots of other things going on but I just thought I'd leave you with that little bit of biology so what converts tell us then about how to age slowly it tells us that the rules we deduce from looking generally across animals or looking at one group don't have to apply to others animals evolve in different ways and they evolve mechanisms to cope with the lifestyle that gives them the best reproductive success also the demands of flight are associated with slow aging a high investment in body maintenance thus a reduced risk of dying from predation makes living longer worth it but of course you have to be healthy right living longer with a good body and that birds have evolved some clever tricks to get sorry I forget clever tricks to uncouple the links between living fast and dying young they live fast and die old so also that tells us now we know why angels live a long time it's because they can fly so that's me done thank you very much right question time can I start about you mentioned parrots and did Winston Churchill have a backhoe that lived to be about 115 or something called charlie which embarrassed everybody by making obscene comments yes well I don't know I guess he probably did and he probably the pirate probably picked up the obscene comments from Churchill himself anyway questions from the audience we've got a roving mic and speak into it like this hi Pat that's great great talk the one of the things you said interested me that that was that birds seem to be subject to less oxidative stress I guess they're just the same sort of mitochondria that we have so is that because they have greater protection against free radicals you're right they do have the same for those of you who don't know the word mitochondria the mitochondria are the organelles inside cells that produce energy from oxygen okay there are other ways of producing energy but producing energy from oxygen is done in the mitochondria as I said a byproduct of that is the production of these free radicals but mitochondria can change how they perform such that they produce less free radicals that happens when they're generating heat for example and but it's also been shown that the bird mitochondrion on average for a unit of the molecule that we use for energy produce less free radicals that's what was being done so there that means the mitochondria are less efficient of course so the bird has to compensate for that loss of efficiency which is probably doing by having more mitochondria I enjoyed talking a lot of course one of the factors which is a form of stress is you mentioned cardiovascular disease but at the moment there is the worldwide I guess now outbreak of avian flu which has had massive impact in some places for instance on seabirds on on vast rock and and so on and I'm wondering if what you're talking about with aging just just tell us anything about resilience when when you have outbreaks and yes possible restoration of populations after mass disease events yes so okay the question was about avian flu and the resilience or not a bird I'm sure you know that avian flu is as you said devastating are seabird populations throughout the world but in Scotland we're losing vast numbers there are interesting differences between species in how susceptible they are to avian flu you don't really understand how it's moving for example you mentioned the bass rock big mortality of gannets on the bass rock we have a gannet colony in the first of Clyde on Ilza Craig and that hasn't happened now that's unlikely to be because the gannets on Ilza Craig are resistant it's probably to do with how the birds are moving and in the case of the gannet it's thought that one factor in the transmission is young birds that are prospecting they're not old enough to breed yet they move around different colonies but they probably don't move right around Britain so it may be just a matter of time for Ilza Craig birds birds have a very good immune system and they tend to be quite resistant to many diseases they carry for example they'll carry bacteria like salmonella cryptosporidia which we would find very difficult to deal with that doesn't make them ill but this particular avian flu seems to really have a high mortality especially in yeast seabirds not so much yet in songbirds but there are big changes I think unfortunately now these kind of epidemics probably happen throughout history you were asking also what will happen to the populations for these long-lived seabirds that take a long time to mature and breed only sometimes just once one chick a year it'll take a long time to recover from that kind of adult mortality unless there's migration which may also happen birds may come in young birds might breed earlier you know they're prospecting often there's no space you take their opportunity so they might recover fast the populations might recover faster but and there might be some birds who are resistant but we have to wait and see on that one unfortunately thank you very much Pat for an enjoyable talk on your zebra finches and the effect of age do zebra finches mate for life or do they just change around every season have a new mate and secondly you mentioned that birds live so long because of high maintenance because they need to fly if you're a captive zebra finch how much flight do you actually do well that transfer your first question do zebra finches mate for life they are an Australian bird they are non-seasonal breeders so they'll breed all the year round which is why they're very useful for research studies but also as pets you need to give them a bit of green and they think it's rained and then they breed they sometimes form quite long pair bonds in the wild in our captive population they don't because we don't want to be overrun with zebra finches so we keep the males and females separately and they'll readily give them another mate and they'll they'll breed quite readily and then the second part of your question was about about flight and yes yes yes yes and when we keep them in a kind of large a berries so that they get they can fly around but when when they're breeding they're they're in smaller cages they fly up and down to the perches but they won't be undergoing any migratory movements around the countryside you know we you have to keep them in captivity so they get some exercise however that kind of thing about how animals allocate resources that's the way they've evolved to do it right so that they're not sitting down at night thinking okay i've eaten this much seed how much am i going to spend on my chila mares how much on growing my plumage there's no conscious decisions they have these evolved allocations because that's what gave you know their ancestors the highest fitness not very much at all maximum lifespan the question was how much does lifespan differ the anybody online wouldn't have heard that question how much does lifespan differ between captive and wild zebra finches not not very much maximal but in the natural environment the average lifespan would be shorter because lots of the chicks will die just after fledging they'll be eaten by predators or or they might find it hard to find food and that will bring the average lifespan down you need a microphone behind you it was a very interesting talk it reminded me of studies and we did some time ago looking at variation within the species a human species you know the four-year difference in life expectancy between Glasgow and Edinburgh or the 10-year difference across the Glasgow conurbation and like the the data you presented we found these these were deep rooted and due to differences were established early in in life and then the analogy that we used to try and explain it was that at any given age glasswegians had more miles on the clock than people in Edinburgh the difference between their chronological age and their physiological age and i wonder if that analogy of miles on the clock you know the two cars with same age but different mileage applies to birds within species so the question was partly was really relating to variation in lifespan even across relatively small scales that we see in the city of Glasgow and is it because they have more miles on the clock i assume you mean figuratively speaking not that some parts of Glasgow people are running about more than others because of course exercise is good for you but early life stress is not and as i said even in the zebra finches it makes individuals more stress reactive and so their bodies are being flooded more often with stress hormones like cortisol in the case of humans or corticosterone does the same job in birds and that has long-term consequences you know chronic stress is changing many aspects of physiology and if you like if you want to say age are fasting aging faster is it in equivalent more miles on the clock and you're running everything a bit faster you're running down faster as the microphone has just been passed from a vegan to an omnivore i would like to appropriately ask what about diet and birds and how does that are there are there vegetarians or or vegans and are there you know more carnivorous birds and if so does that affect uh yes diet diet diet is interesting um zebra finch is a seed eating bird so again that makes it great in captivity we're not having to go out and catch insects or worms uh in order to feed them um do carnivorous birds live longer or shorter than seed eating birds i've never seen any studies specifically on that birds of prey don't they're not a standout group in terms of their lifespan um their standout group perhaps in terms of the agility of their flight uh you know something like a sparrow hawk is an amazing bird when it comes to its flight performance but i don't think it's you know living a lot longer than the bird of similar size who's eating grain and there are some birds which are only eating grass most of their lives and they're you know some of the geese really long lived so i don't think there's a straightforward difference but i've not seen a detailed analysis of that could be interesting um you mentioned that the the lifespan of a the partner of a bird that had been stressed in early life also their life their lifespan was shorter too which was quite surprising actually yes um did you have any theories about why that might be yes we we hadn't to be honest expected that effect um we had expected it might be the other way round uh but you know there would be a kind of mitigation of the fact of the lifespan effect by the partner instead uh you know that that didn't happen it was uh and and if you had two of those early life stress birds bringing together you know it was even the adversely affected each other um i had a postdoc who looked much more at their behavior and some one thing that the partner of a bird or any other species can sometimes do is have this kind of buffering of responses you know it's kind of comforting or it can have the opposite effect which is they both become jittery and that's what seems the most likely explanation you know if it was the case that um in the natural environment this exaggerated response to stress is beneficial because the bird or organism has set its responses according to its assessment of how dangerous the environment is it might be advantageous for the partner to do the same it's just that the environment isn't dangerous and this matching of the early and later life environment may be an important part of seeing that effect remember we only exposed them to stress early in life and then it wasn't a stressful environment and it would be interesting to do the same kind and we've done it to a degree but to make the adult environment also a bit more stressful and see you know if that actually gives them some kind of benefit relative to an individual that isn't prepared for it. Pat it's a bit of a fall-up to the gentleman who asked about meat eating birds as opposed to grain eating or grass eating in the multi disciplinary graph that you had the very complex one one bird was away above all the others in lifespan and that was a condor which spends most of his life not exerting any effort flying around looking for meat to eat and has got no predators very a fairly stressless life as long as humans are killing beasties below or somebody else is killing them is this not some evidence that in fact living a very relaxed life eating meat give you a long life. I take it that's your philosophy. Okay it comes back to the evolved response right the condor is still it can fly it's still got to be able to take off but it's big enough as you say it doesn't have a lot of predators now but yes these top predators are likely not to have to spend so much time evading things and good luck to you sitting back and eating meat probably doesn't do your heart any good but no it's interesting observation. Hi just going on on the question of diet is there any evidence as to what bread particularly white slice bread in bits can do to ducks and a pond or similar food that people give to animals to birds. Yes feeding bread to ducks is it good for them it won't be great for them if you think of the gulls that hang around Glasgow eating chips and ice creams and so on there have been studies showing that you know these they're not as healthy birds tend not to get really fat which is interesting they have controls as the most animals on body mass however another thing about birds is they're capable of putting on an enormous amount of fat for their winter migration right so they're really pile on the fat and some birds will undergo a really long migration just using that onboard fuel if you like but hanging around Glasgow eating chips or or bread not a good plan and they're busy you know their health is not so good and feeding animals the wrong thing is always bad you know usually they'll take it and it's not good for them but I don't see loads of dead ducks I don't think the bread is too bad but a lot of places now offer special duck food to try and stop people giving them and the gulls on the rubbish tips I did a lot of work with them and because they've got a fantastic immune system they could eat a lot of this terrible stuff but some of it would really get stuck in their throats and kill them sometimes and then or else they would go and digressing a little bit but they would go to Moogai reservoir and throw up everything they thought twice about into Glasgow's water supply. Yes hello very interesting talk thank you just to continue that earlier question is the abnormal telomere specific to birds you know the great conundrum that we've heard about in other talks about you know people in Glasgow ageing earlier in different parts of Glasgow is that finding that they've got in those and just a comment for those who were asking about diet if you read any of Tim Spector's excellent books he analyzes which foods help the so-called blue populations in the world which are the longest living which contributes to that source. It kills a lot of the myths. There are a lot of studies that are going on on telomere land in diverse social circumstances including in Glasgow and you do see effects in the predicted direction because early life stress can shorten telomeres sometimes people ask well you know I said that there are enzymes which can elongate telomeres one reason that in many animals large-bodied or long-lived animals that doesn't happen these enzymes are inactive they're not produced in the cells in our sort of in most of the body because if you have if you allow a cell to carry on dividing there's a danger it will become a cancer cell you have to control that so you know cells divide more they get occasional mutations because the DNA replication is faulty they can then if they divide lots and lots of times accumulate enough mutations to become a tumor cell but telomere shortening will knock out those cells before that can happen most of the research on telomeres is done by cancer biologists it's only relatively recently that it's been looked at in other kinds of animals so there's this huge areas of interesting biology there diet inspector gut microbiome all very interesting stuff but the gut microbiome and diet is not my field any more questions yes I think it's a bit the last one so um thanks very much for all of the answers so far they've been fascinating you have mentioned that shorter lifespan seems to come from for example stress and then being more stress aware is there any direct benefit for the survival the species from the shorter lifespan so I mean rather than it being a cause of other things that are a benefit I just want to make sure I understand your question are there are you asking are there benefits to a shorter lifespan yes yes exactly so I'm asking does the shorter lifespan help the animal survive directly by being shorter in some way is there some well a lot of interesting things can happen there that sometimes in certain circumstances when exposed to a stressful environment breeding starts earlier right so in figurative terms it's almost as if you could see the animal nose that its time is limited and it gets on with breeding now when that happens in an evolved way you're going to get a whole different kind of life history where reproduction will start early much more effort will be put into early reproduction rather than later reproduction that's part of the evolution of animal life histories is the scheduling of reproduction but for species within a species where you're then looking at environmental effects you can still sometimes see a shift towards earlier reproduction of course other things you know a shortage of food can turn off reproduction and sometimes that means a longer life because you're not devoting energy to reproduction anymore but evolution will have nothing you know you're you're out if you don't reproduce in evolutionary terms so there has to be what we in biology call a Darwinian fitness benefit you have to have successful reproduction for that kind of strategy to become part of the evolution of that population so these are you know things that biologists are wrestling with all the time nature's diverse solutions that it comes up with oh that was the most wonderful nature you can see from the number of questions how fascinating people are and I have this enormous pleasure of giving you