Andre Dhondt, Interspecific Competition in Birds.mov

this is a production of Cornell University competition predation and mutualism are the three main types of biotic interactions between individuals of different species all three exert powerful selection pressures that shape communities however the true importance of interspecific competition in nature remains a controversial and unresolved question during a chats in the stacks book talk at man library dr. Andre don’t discussed his new book interspecific competition in birds which highlights the impact of both past and ongoing interspecific competition on the coexistence of species the lessons learned are timely as ecologists work to understand the many factors that influence global biodiversity and to model the effects of climate change on populations they may learn a great deal about species interactions from our feathered competitors before I start let me first say a few nice things about the place in which we are man library you heard it I come from Belgium when I wanted a paper that I needed to read I would fill in a interlibrary loan form and six weeks later I would receive a photocopy today I simply turn on my computer go to the manna library website and download the PDF makes big difference i must say i don’t know how people wrote books in the past without that facility but people did actually so what i want to do today is two things and they will be intertwined i want to talk about hi how the book was written why the book was written and then also clearly in that context i will say a little bit about what’s in the book and so what were the conclusions are so the book started some extent by accident in 1998 I was at the IOC the intl adulthood conference in South Africa which is big conference which happens in every four years and I gave a plenary lecture about my work on competition and it’s there and after the the talk John Krebs came to me and he said Andre have you ever thought about writing a book about this I said no said well I said but I said if I were to write a book it would be about it the specific competition so John of course being who years contacted the science editor of princeton university press which came to my office it’s up woods and saying hey you know John Krebs said that you might want to write a book about this maybe you should we should talk about that I said yes yes maybe so a couple of years later I had a sabbatical leave coming along and I said okay maybe i’ll try to see if i can write a book at all so I conduct I contacted the guy from Princeton University Press again they said you know are you interested i’m going to try to do this he said well we known we do this kind of book okay so i went on sabbatical leave to Fort Collins with John wins and one semester and the intent there was to see if I could could write a book meaning could I construct a table of contents therefore had to read what was published and basically what I did for month or two I read 50 years of literature in a month or two to get to know what was there and think about it see how could structure it and when I left after the end of the semester I had written not every table contents but half a book that was very pleased with myself but I can came back to life ornithology and at that time I was very much involved i still am actually with the long-term studies of disease in house finches and i had no time at all to to think about the book for several years then my next sabbatic came along and I said okay and I’m going to take a full year and see they can finish the book and where can you go for a full year where the silent Sun France is not a bad idea it says I went to to moberly which is here over there some france and it’s not a bad idea to foot part of the world lots of medieval cities nice landscapes beautiful flowers and then you can learn things there and so what I learned there observing and good food of course good food from threat and then you can learn how to park your car right so you drink that’s how you park your car in France it squeeze it in I drew the line at learning how to jump to avoid but bur bulls or to jump over them I did not do

that ok but what I did do I worked at the sandton ecology function deliver it even more per day which is a large reaches center funded by the cns in arrested equivalent of NSF the difference being that in francis in areas founds their own research institutes Brezhnev doesn’t do that and the this Center for ecological research has a hundred scientists it’s a good place to go at some point there were six American professors at the same time visiting while I was there so it clearly it’s a place which makes sense to go when you want to interact with colleagues a bunch of people I know they’re of course this was very welcoming so when I spent the year in the Institute my office was there on the third floor there okay so where do we start well where is the where are the IDS that we know what they’re thinking about interspecific competition and you will get a number of slides with some text where I cite things that way I do justice to what people they say and think and so in 1989 was a really interesting volume which was published by the British Geological Society which was called ecologic concepts and there were a bunch of chapters clearly about different things in the chapter on competition which was written by law and what Watkinson said that it was difficult to perceive a real sense of progress in our understanding of the role of competition nature 1989 and then they say that you know we can really there is it say that people have done anything useful in the past there is no you cannot point to an accretion of knowledge to empirical questions clearly framed and in ekivoke unequivocally answered rather we are left with an impression of a subject moving from one world view to another depending on the influence of the prevalent protagonist what’s really interesting for competition buttons for science in general that individual scientists can have an enormous influence where people are allowed to think and actually and I give some illustration of that at the book when I review the IDS about competition in my first chapter and what are the two the two IDs are at competition either it’s important or it’s not important so it’s important caddy in this books on competition it’s a force as fundamental to ecosystems as the gravity is to planetary systems that’s pretty important and then the other opinion really is okay it may be important but until proven we don’t believe it it exists as such and proven by field experiments okay so thats caddies book the second edition was interesting I have them on my desk those two books the first edition which is 200 pages the second edition is 550 pages so he felt inspired and so and he defines and I like acted his definition of interspecific competition which is basically the negative effects which one organism has upon dollar by consuming or controlling access to a resource but this limited and availability controlling means in an interactive there is a behavioral component to the interaction consuming basically means if species a eats something which is a little bit availability it’s not available for species be okay so when on the one hand caddy is completely convinced that competition is absolutely essential and fundamentally important in ecosystems sweet of critical people which included Underwood from Australia John wins and Nelson Houston which is Nelson’s father one of my heroes in science notes on house and junior senior we wrote critical reviews about the evidence supporting the existence and the importance of interest rate competition and you know the type of critic criticism they gave this is not exhaustive hear about this is some of them I elicit here is first one circumstantial evidence from descriptive data cannot be used to exclude alternative hypothesis what does this mean if two species have allopathic distributions this can be because they compete with one another and therefore cannot coexist or they can simply be because they are two different species that evolved separately you cannot exclude one or the other hypothesis so you can’t use it as evidence that competition is important the other the second argument is that competition may

have been important but no longer is important no longer plays a row the third criticism which I think was was valid in those days was that very few field experiments to test for the existence of interest to decomposition we’re done properly didn’t have controls didn’t have replicates and they usually went on for a week or two sometimes for a month or two but rarely for very long so very few field experiments we’re done properly and then the false criticism was interesting is that the species that were selected to the to test the existence of interest a second position experimentally where a biased subset and it’s true if you look in Vince’s book flight in 89 he lists the experiments competition which existed then three quarters are using cavity nesting birds why cavity nesting birds in many cases to use nest boxes and you can play around with s boxes and do things and it’s not because competition is important perhaps in cavity nesting birds that is a generally important in nature so the species select is a bias subject okay so competition okay thank you competition occurs when resource are limiting and this limitation has an effect on fitness or abundance the question is can we observe it and can we prove it exists experimentally in the large team which is recurring in my book is the use and the need for field experiment to run properly okay now that’s an interesting problem with competition because if you look at predator-prey interactions or the herbivores or parasites I mean you just observed that it happens right just no discussion you don’t have to prove that predation exists you can observe it you don’t have to prove that the mosquito is taking blood from the bird you just observe it even from utah listing interactions you can often observe that exists so you can ask different questions you don’t ask the question can do the scope predation occur you can ask the question what’s the effect of predation on the host on the predator etc etc and the problem with with competition is that although you can observe aggression this doesn’t mean that competition is taking place right now in this case this is the example of aggression between over fight between two woodpeckers and you see this this flickr he holding onto the tip of the thumb is to red-bellied woodpecker in this case it is linked to competition because they are fighting over a hole in which to breed and raise only one hole in just two birds so in this case the flickr who is the more aggressive species will exclude the red-bellied woodpecker from the cavity and the red-bellied would will not be able to breed to just an effect on fitness so this would be an example of interspecific competition but it is rare that you can observe this so easily so there’s now a big paradox on I have four or five slides about this to make the point really clearly the paradox of industrial competition is that it is so important that you can’t observe it and the reason you can’t observe it that is so important that as soon as exists the speed the species will evolve to avoid it they will either go and live in different places or you defuse different resources so it is transient and that’s a point which has been made many many times I was very I’m very fortunate to be at Cornell and have him on library and in man library we have the book by Gauss from 1934 and the remembrance started in it in the 2001 started preparing thinking about my book I came to the library and borrowed Gauss’s book and I helped this book in my hand I said oh God well unbelievable I must say when I use it again the six years later it I could just read it online that completely scan the whole sequence clinical dreams actually anyway but to be have this book here and Gauss is one of the people who played a fundamental role in the development of ID’s a route industry competition he’s also the guy who did the first experiments which you find in all the boot textbooks of ecology which we teach every year to interrupt introductory ecology classes the experiments with girls performed in the experiments were to test mathematical models which had been developed in the nineteen twenty-seven 1928 by a local Volterra couple of italian scientists but what’s interesting about Gauss’s ID that he formulates here is that if two species that as a result of competition two species that are similar don’t do not use the same resources basically and he gives us real nice example from this

from some terms that some Russian colleague of his studied and said that although you would believe when you look at them they eat the same thing when you look more closely you’ll discover they eat different things they use different resources so the systematic the intensity of competition is determined not by the likeness that’s the closely the relatedness of the species by by the similarity of the resource they use and this has been reformulated as the I pinner ddd principle of competitive exclusion Gauss’s principle that we all use in all the textbooks of ecology always come back to Gao society okay it’s interesting that Gauss are never formulated the principal companies inclusion the way we use it today that’s actually as close as we come to this formulation ok so the paradox of competition is that the evidence that we use to prove the existence of competition is in direct its indirect because competition is transient when it occurs and the species we evolve to avoid competing further the result of that if that is true you cannot test the existence of interstate competition experimentally because today when we observe nature this piece that coexist do not compete if this hypothesis this assumption is true and to show you how many important people believe this is true I give you a couple of quotes and many of you have met here Wilson this one he was a bit younger with bill bill brown and so they wrote a review on character displacement which is an effect of industry competition and I like this quote because it’s the way it is written it’s so different the way we could drive today is it in the specific operation of the direct don’t spicuous on Nikki vocal kind is apparently a relatively evanescent stage in the relationship of animal individuals or species and therefore it is difficult to catch and record what we usually see is the result of the compaq on the contact you dont’t of contact that’s Brandon Wilson David lack 1971 published a book and Dave attract was the leading only toll assist ecologist and Europe definitely possibly in the world in those days he wrote multiple books in this book a collector echolix isolation in birds in Chapter after Chapter four every family of birds he describes how the species can coexist without competing and actually this this this illustration here by robot Gilmore illustrates the work which David like that in Oxford in white and woods and make the point that although several species of tits coexist in the forest they use different resources because they forage in different locations the blue tit hangs upside down from the foliage and thin swigs the great that forges mostly not only on the ground and the mast it sits somewhere in the middle of course the simplification but this illustrates likes ID this is how it is possible that those species coexisted the same forest although at first glance they use the same resources and Chris parents when he wrote the book on tits in 79 explained how this comes about over long periods of time natural action has favored those individuals that have evolved ways such to be different from the others 1979 so the idea that the competition does not exist cannot be observed is something which is still relatively recent okay so how did I do this then how do you handle this I said ok let me after reading the literature I said let me set up a number of necessary conditions and number of sufficient conditions related to interstate competition if any of the three necessary conditions does not occur we do not need to discuss the possible existence of in this competition because those they have to be to exist and what are those three conditions well first one or more or resource are limiting if we source are not limiting the canopy competition in trans-pacific competition occurs me nearest competition between individuals of the same species for limiting resources in the older formulation when I was in gratitude this will be looked at density dependence and population regulation which is the same thing with different words and then clearly for intercepting competition to exist resource use of potential competitors must overlap if the two different speech do not use the same resources there will not be competition and then sufficient conditions are basically evidence for the existence of

competition namely that if resource use by one species affects the availability for other species so if species a is the food it’s not available for species B and then a stronger evidence for the existing competition is the effect of fitness or the effect of the effect of competition if the density of one species increases that fitness of the other species will decline and then finally perhaps the strongest evidence is that the presence of a species affects the distribution and or abundance of the other species so and I structured my book around those those those six IDs basically so in chapters three four and five I look at the resource which are potentially limiting which is food space and math science and I look at the evidence in the literature that exists that shows when people ask the question is the limitation of space history is space limiting have people have done experiments to test this I report that and the answer is yes we find a lot of examples where dress competition fight for space for food and or for no / science what’s interesting about the nest site one is that when you look the nest sites are also limiting for open nesting species because normally we always think our nest sites are limiting only for cavity nesting species although some people believe actually cavity less things are not limited but that’s okay but Tom Shanna did beautiful experiments where he proved that open nesting species that the nest site for an open Esther actually is a very viable resource and that it’s limiting and that you know that some species cannot use the best nest site because of competition with the different species that’sthat’s dinner that’s something which deserves more more more study okay can we document intraspecific competition the answer is yes of course I would say but in a question is for which which of the population processes and what’s interesting when you review this exhaustively is that even it’s within a single group of animals birds you find that depending on the life history of the species the population processes which are affected by interest recondition are not the same long-lived species do not typically have effects density and effects on reproduction but they have tend to depend effect on dispersal short-lived species often have ten sleep and effects on reproduction and/or perhaps on mortality and actually what I do in that chapter that I review a number of species for which that have been studied for the entire year and all those process have been looked at to see which one of those process are the ones which are most affected by in transfer the competition and that’s something you know which which I think deserves to be done more systematically than I did myself no just to frame that chapter which maybe i would i might do one day is to do an exhaustive review of literature to see for different life history strategy of a species which of the population processes are most affected by by infrastructure competition the problem is that there are very few studies of animals where we we study them year round and like you know and dressed like dustin one of the studies that I isomerize is by by the combs muzu black-throated blue Warbler where he studies the effects of competition both in the breeding grounds in New Hampshire and the window grounds in Jamaica and he finds effects different effects on different components of life is to be a different different parts of the animal psycho so yes so that that’s that chapter chapter 6 and chapter 7 okay now that’s in the food and the reason this chapter food comes here is that enormous amount of work has been done where people have asked a question but fortunate when when the species is by itself or with the potential competitor does it look for food at the same locations and so to descend so that’s when I combine their the the Virgin HDD direct evidence and also there’s a lot of observational data there which are very interesting what’s very interesting when I read that at some point was a Douglas moss some of you might know him he used to work on birds he looked at competition and forge ignatius between birds and so in his give us young guide in 1968 and he

published a paper said generally pygmy nuthatch is affected by the presence I forgot which Warbler the girls foraging and quite strongly said dress competition between the species and then a couple of years later writes a paper and is much more careful howrah phrases this so I send them an email said Doug what happened what happened between 68 and 72 why did you change your mind or why did you rephrase the certain that you had do something much more careful and it’s the well in those days for a young scientist I’ve talked about the late sixties early seventies for young scientists making the claim that industrial competition was really important what’s dangerous for your career well so that’s a citation have somewhere in my book also that email be kind of interesting to see that the power certain individuals have you know what you’re allowed to think interesting okay then chapter eight is a big chapter I review exhaustively all the field experiments which have been done on industry competition involving birds some of which involved birds an insect or bird and fish or birds and mammals but all those birds are always involved and then chapter nine i summarize my own field experiments on competition between great and blue tent in belgium the you got chapter 8 and i summarize briefly so it was about 200 about 100x field experiments have been done that I discuss that I felt I probably missed a few but I don’t think I miss too many today with the web of science and the way you can search your literature it’s pretty amazing and my students know that I tell them you should do your homework and I can’t allow you to miss literature you have to read your stuff and find it and read it and remember it that’s the important part okay so what about the hundreds and I split them here in this this summarizing table in those were experiments where either numbers or resource were manipulated 75 and you see that most of them but not all of them show that there is into especially competition between the species in nine experiments there was no evidence for competition at all and in 13 it was evidence for facilitation one of the interesting things which has happened in the early 90s was bye-bye finish colleague and friend become mekonen who did a fascinating experiment he northern Finland he had some islands and in some of the islands he hadn’t nest boxes to increase the number the number of tits that were there in winter and other islands he removed the birds and then he watched where the migrants would arrive in the migrant birds and the derivative us competition the migrant bird should go on the islands with its had been removed but he didn’t find that he found the birds settled when it gets by present rather than where the debtor be removed and he called this hetero specific attraction and the ID the logic here is that migrants which breathe in the finals don’t have much time to make a decision where they will breed they arrived they have to stop testing almost immediately so what information they use who where do the birds that state spent with here live where do the build survived there must be good conditions there therefore let me settle there also and Michael and his colleagues have done a whole suite of experiments showing the facilitation occurs over and over again it is more complicated more interesting than that but that’s the basic idea so so that’s a then the other in the second row here is playback experiments where you to test for the existence if one species to species cooker you play the song of one species will the other species respond yes or now and the answers often but not always see that sinner often but not always and that’s actually something which deserves to be looked at also in more detail they have not been done too many experiments and especially not in tropical areas or in mountain ranges okay one of the things which which clearly we’re all interesting is the effects of climate change on what happens in nature and so one of the things which which when I didn’t mean I does long-term data from the tits in Belgium and in 1977 I published a paper when I drew this is a bit technical but till just believing what the bottom line is correct I drew isoclines greater density and gluten to get to another each point is the number of greats and blue turds in the same site in a particular year and you can calculate Isaac lines through those points and the way those Isaac lines intersect tell you if competition will have an effect that this piece calcio

exists or not it fortunately we know that grated saluted coexist fortunately I supply show that they do actually coexist those was lucky ok so does 1977 we’ve studied continued to studies on tits they’re still ongoing actually in Antwerp and and then in in just after 2000 a bunch of us decided which would put all the data ONTAP mice from Europe together and from 1882 to thousands we had study sites in England Belgium the Netherlands France Finland Germany kousaka and Russia when we analyzed and we had data for 414 study sites for great and looted and they look to see if there was an effect on laying dates because of changing climate and their answer us yes but not always there again I’m not going to the details I can explain that you’re interested so we found that through our effects of climate change on at least laying date and clutch initiation date and also we found since then that actually on the the whole nesting cycle behavior has changed to some extent by several days actually on top of the late linked to climate change so then we thought well maybe this could have an effect on the outcome of interspecific competition too and so will stand set colleague of mine in Oslo said okay give me your data I will have somebody play with them should by now it’s about seven different mathematicians have played with them and they have produced some interesting equations which we’re not going to discuss but basically that is the data this is one study site in Belgium over a period of 45 years and you see the red points on great it’s the blue blue line is blue tits and you can see over the period of 45 years created numbers have gradually increased although they fluctuate from year to year blue denims have decreased we know dress competition with two species does competition play a role in this change in abundance of the two species so what’s what this drastic Kirsten did it so he calculated the isoclines which as you can see look very similar to the ones i calculated 1977 and the isoclines still say that the two species coexist in a stable fashion and those are the equations which he cut which he calculated and then what he did he looked at spring temperature april temperature and so for part of the periods in this turned out to be the critical temperature for april temperature 8.6 degree centigrade if the temperature in april is warmer the model to calculate coexistence changes and the isoclines change in such a way that blue tits barely survive so the prediction of this model is that because of temperate change in april the coexistence of greater than blue tit is endangered and blue tits might go extinct in a closed system that this multi not going extent but they might go if those things continue and become worse so the intensity of competition can change with changing environments and in the book I list a number of examples in plants and other animals that show effects of climate change on coexistence on the intensity of competition which have become worse can become better one interesting reference which i found was about about 40,000 years ago you’ll remember was it called them and DD the paper that says that because of this cold spell 40,000 years ago through the existence of interspecific competition between modern man and the under Taliban the underdog man went extinct so that that’s what competition can do ok so we have shown that competition does exist the conditions are fulfilled the evidence is there so now the next question that I want to address is can the existence of Industry competition cause nevelocity change clearly to show that experimentally one needs long-term data and so and to me to some extent this is we coming back full circle whereas on the one hand 50 years ago people said species that coexist do not compete because they compete in the past and have become different implying that because of competition this caused everything change I find that there is compelling evidence that competition does exist is ongoing therefore you would expect an evolutionary change in certain populations in certain conditions and clearly where we go first so can we identify selection pressures how rapid does it go and typically we go first to wear to the Galapagos Islands be the ground Peter and rosemary grounds

work and this is particularly interesting example it’s not experimental but close enough so what does this show this shows you big size of the medium ground Finch and this is time and what you see is that here in 1977 was a very severe drought in the linear in a mini effect and the majority of the individuals on the island from daphne island died and only the large big bird survived but except of three small big dreamers also built okay so here was a severe an extremely rapid evolution a change caused by a lack of food and intraspecific competition competition between species the individuals of the same species okay over time there’s several there they had seven recurrent events like that and around here a second diamonds Finch settle of the island magneto streets the large beaked ground Finch and for a while nothing happened the medium medium ground Finch to the big size didn’t really change and he had again an extreme drought actually two years in a row where a large number of the Darwin’s finches the medium finches died because of lack of food competition but in this note was not only competition with individual the same speech was also complished with individual over different species and in this case a different species had much larger pic so the magnet rosters was able to eat the remaining large seeds which were there therefore having them no longer avail for the medium sized Finch and only the median science fiction which small big Scott survived and we had here DD the opposite effect during our competition here this was caused by n transpose V competition this was caused by interspecific competition so that suggests that in da Silva competition can cause revolution change very rapidly depending how you calculate its either over 20 years over two years but it’s very rapid regardless when i started my experiments on tits in belgium one of my objectives was to manipulate densities of the two species and to see if this would result in evolution a change in in the the birds and I give you an example for the blue tit this is TAS links at the length of the leg this is 3 study sites and what I did is here there was a 15-year experiment and what I did in nineteen between 88 and 1989 I changed the density and therefore the the intensity of comp interspersed competition in this one plot in plot T whereby did not change anything in the two other plots and what happened is that in the situation that this five-year period in which the intensity of intra and Inter split competition was really high there was a selection for larger blue tits large individuals but isn’t the other two sites nothing really changed so also this is a very rapid evolution change when you change clearly this is artificial it is playing around with nest boxes and manipulating densities but it’s a field experiment you don’t control anything else and they’re also you see that a rapid evolution change can happen because of a change in the intensity of interspecific competition so what do I conclude from from writing this book well in the industry competition happens today we can observe it its ongoing not everywhere not all the time but it’s ongoing I I will not go in detail but there’s no real bias regarding the tax are used and as regards the quality of the field experience it is amazing how many really good field experience have been done the last 10 or 20 years it is unbelievable it is either that the students are better trained or that the bell experiments no longer get published which is this all birth but clearly the quality of the field experiments in ecology as has become phenomenal I would say ecology has come of age field ecology has come of age fully I’m sure for botanist I mean this was already then on going in the spirit of competition can cause rapid evolution ii changes and it’s generally important force that we must take into account when we evaluate the community structure okay now hold on don’t go away yet just just started to talk so here we go you write the book manuscript so half and now i can find it can i find the publisher so i know that we knew that

Princeton University Press Nolan was interested they do not long do not book like that and you know I did find that publish because the book is here but how does it happen well i contacted oxford university press and I said you have this really nice serious the ecology and evolution ecology evolution serious might be interesting to my book in there and actually I talked to several the other editors of the series destroy alien areas maybe you know if you want to do this you have to do this and that and the other which I did actually and then six years later went back to Oxford to say okay now I have manuscript almost finished are you still interested this error not for that series because it’s only when I Commission those books that we published about seriously but we have a new series Oxford even apology maybe it would fit in there so what happens then the publisher gives you a questionnaire and you have to write a prospectus which explains you know what the book is about why anybody should care about this book what other books exist in the field which are similar and therefore would compete this time with an important concept here and then you know and then what is the structure of the book and can you write half a page about each chapter etc etc you send this prospectus to the publisher and the published sends it out to a number of reviewers now two things which happen so so the first reviewer said you know question 5 is the Eureka run public in this book publishing haha and that’s really kind of Sid actually this I read as I said interesting the book is somewhat dated top come to the senior knows no one was interested in ecology although don’t is ok to write this book it’s about 20 years too late ok fortunately three other reviewers said yes you should do this book and this is so this is some some nice things that why this book should be done so when I received those comments from the reviewers I am in Oslo after meeting fondled sunset who had his 60th birthday and to have a feast for a 60th birthday he invited a number of his colleagues with whom we had collaborated for a three-day symposium which was it was phenomenal symposium and then it ended done with a dinner and a Calgary to it is true Norwegians gave speeches which never ends the dinner was finished three o’clock in the morning only three or four speech so that’s it anyway so I read those comments in my hotel I go to the symposium and between two talks I sit next to Peter grad I said Peter I just received the comments from the reviewers one is really bad but the three others are good and one is really really useful the video gives me useful really helpful advice how to change certain things in the book he looks at me says yes this was me so I thought well thank you i’m glad i said was helpful rather okay so the book get published and then you know Daniel you wait what will people say about your book goes you know I can say all the nice things about my book here because you know nobody well you can talk back to me in a moment but you know but then you wait to see what reviewers rights and today there’s two reviews have appeared in april one in terms of ecology evolution and i would say i couldn’t have written myself was real nice and what what’s interesting the point she makes and actually i don’t know this lady I’m good enough I don’t really know her but you know when I meet her ever say thank you she’s what she points he makes it that though it is more than just for an etiology which clearly was the objective of writing the book I mean I’m an only told gist yes but I’m the college its population ecology behavior ecosystem and evolution ecologist I’m all of the above I’m not interested I’m interested in both I know more about birds and most other groups of orders but when you do something in the science you want it to be more generally useful rather than more specifically so the fact that she says that the book is more than just an only told his reserve resource it’s kind of nice so I think that that’s so that objective was a pain and then two days ago I got this comment from cannot err from university of northern northern British Columbia where he says it’s a good book also so he liked it too so having said that i will stop I will if you have any questions I may be able to answer them thank this has been a production of Cornell

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