I had been looking for rabbits lately, because of this: the cat had switched to hanging out by the upstairs window, the better to observe the just arriving Juncos (snow birds, it is fall). She had previously spent most of her time observing rabbits from the lower, ground level windows, until just the other day when, rather suddenly, all the rabbits disappeared. Until then, there was always a rabbit or two. In fact, the entire city had been recently invaded by rabbits, according to several reports, and now they seemed to be disappearing quickly. This, I assume, means that the coyotes finally got busy. Or, an epidemic of tularemia. Either way, something happened.

I once had a cat that was partly outdoors on Cape Cod. Well, the cat was indoors, but would escape. We’d go looking for it and always find it in a bush (a different bush every time) surrounded by no rabbits. All the other bushes would have rabbits nearby. But not the one with the cat in it. (Until, again, the coyotes showed up and ruined the rabbit-test method of finding the cat!)

Have you seen the film Dead Birds? See it if you can. This is a very important ethnographic film, of the old style, by Gardner, of a place in Highland New Guinea. Part of the story actually has to do with live birds, not dead ones, and how they are used by sentries at the outskirts if the village lands, during times of conflict, to detect the arrival of enemy combatants. You watch the birds, and you are watching the hidden predators.

Or you can listen to them. Or you can listen to the monkeys. Anything with an alarm call. I could engage you with story after story, if you and I both had the time, of finding very interesting and elusive critters out in the bush, mainly in Africa, by following up on the predator avoidance behavior of primates or birds.

And, this brings us to what I think is one of the best bird books ever.

What the Robin Knows: How Birds Reveal the Secrets of the Natural World by Jon Young is an exploration of nature based on this premise: the robin knows everything about its environment, and this information is regularly conveyed via the bird’s call, or its behavior. By observing that behavior or understanding the robin’s vocalizations, you can poach that information and also know a lot about the immediate environment, which may be your own back yard, the area near your camping site, the wooded gully the enemy may approach you by, or a nearby park.

And, of course, it isn’t just the robin, it is all the animals including birds, insects, and everything else. But Young is talking about birds, and it is certainly true that in most or possibly all habitats, it is the birds that, owing to their diurnal and highly visible and sound oriented nature, are telling you all this information about your mutual surroundings as well as about the bird itself.

To me, birding (and nature watching in general) is not so much about lengthening one’s list (though that is always fun) but, rather, about observing and understanding behavior. Young explores this, teaches a great deal about it, and places this mode of observation in the context of countless stories, or potential stories, about the world you are sharing with the birds you are watching.

This is a four or five dimensional look at a multidimensional world. Lucky for us humans, as primates, we share visual and audio modalities, and mostly ignore odor, and we have overlapping ranges in those modalities (to varying degrees). But birds fly (most of them, anyway) and are small and fast and there are many of them. In many places we live, we are the only diurnal visually-oriented non-bird. Indeed, while I’m sure my cat communes with the rabbits at a level I can’t possibly understand, I’m pretty sure I get the birds in ways she could not possibly get her paws around. (Which is why we don’t let her out of the house. She would prefer to eat them, rather than appreciate them!)

From the publisher, about the author:

Growing up near the Pine Barrens in New Jersey, Jon Young studied as a tracker and naturalist. For three decades, he has taught and mentored children and adults, combining Native skills practiced worldwide with the tools of modern field ecology, emphasizing the nearly lost art of understanding bird and animal language. The founder of OWLink Media, 8 Shields Institute, and the Shikari Tracking Guild, he consults with programs around the world. Jon has written or produced numerous books, audio, and multimedia projects. His website is www.birdlanguage.com. Married with six children, he lives in the woods above Santa Cruz, California.

Lots of science in this book, well documented and referenced. Simple black and white but very engaging graphics. So far my favorite bird book of the year.

First, the innate vs. learned part of the question. This is a false dichotomy. We have evolved to learn. We probably have “built in” mechanisms to learn new things. This means that when we have learned something new, that new skill or information is a product of something innate and something from our environment. (See: Culture Influences Brain Function and IQ Varies With Context.)

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The degree to which this is important should not be underestimated. Humans pay a high evolutionary cost for this ability to learn. We have developed over evolutionary time a mostly novel stage of development that we call “childhood” during which we are vulnerable and demand a great deal of parental investment, far beyond our nearest primate relatives. Childbirth in humans is dangerous to both mother and child compared to other mammals, and this is in large part because of our large (but mostly “empty” brains at birth. Childhood involves the internal organization of that brain due to experiential learning aided by built in learning mechanisms. This takes years, and results in a young adult adapted not to our paleolithic past, but to our current cultural environment. (See: The Oystercatcher and the Clam)

In other words, we are adapted, by evolution, to be adaptable to the particular context in which we live. For this reason, our actual (in the sense of current, now) set of survival skills are adapted to the present because we are shaped by evolution to be able to do that.

Having said that it is still true, as demonstrated in the National Geographic special, that we are products of our past. We are endowed, for better or worse, with automatic reactions to the environment such as the stress reactions and the famous “four F’s” of fighting, fleeing, feeding, and sex. Our learned abilities incorporate these basic limbic (brain and endocrine) functions, but these functions are powerful and often produce less than ideal results.

There is a debate in evolutonary psychology and related fields over the degree to which specific abilities, including survival abilities, are shaped mainly by our paleolithic past vs. our cultural and more immediate developmental past. An example that is sometimes used is the bartender vs. file clerk test. Here’s how that goes, simplified.

Several subjects are given this problem. You are a file clerk and you go on vacation for a time, and a temp takes over your job while you are gone. On your return you have the sense that the temp messed up some of your files. You are faced with a set of labeled folders that may or may not have been filed incorrectly. Your job is to open the absolute minimum number of folders to test the hypothesis that they are correctly filed. there is in fact only one correct answer to this question. A majority of subjects fail to arrive at the correct answer.

Alternatively, several subjects are given this other problem. You are a bartender and a specified number of people (the same number as filed in the previous setting) are sitting at a table in your bar asking for various drinks. Some of the drinks contain alcohol, some don’t. You suspect one or more of the individuals sitting at the table are lying about their age, so you need to ask for ID. Your job is to ask the absolute minimum number of people for their ID. There is exactly one answer to this problem, and the underlying logic (and answer) is identical to the file clerk problem. A majority of subjects arrive at the correct answer.

Those who put a lot of stock in our brains being shaped by our paleolithic past believe that this is because we evolved in a context where identifying liars is important, so we are innately good at that, while file clerking is a modern endeavor, so we are not evolved to be good at that. The alternative explanation is that we each grew up, as cultural beings, in an environment where learning to detect liars is important, so we got good at that, but very few of us grew up as file clerks, so most of us are bad at that.

I personally lean towards the latter, and I look at the costly trait of childhood as the mechanism by which this situation emerges.

The short answer to this is, I’m not really sure, but I think it is helpful to put aging, and changes in human patterns of aging, in a broader anthropological and evolutionary perspective.

When we look into the past, it is too easy to compress our ancestry into a caricature of primitive humanity, and based that conception on the wrong model. For example, it is said that “people were shorter back then.” Often, that is true, but the shorter people were actually poor urban dwellers in late medieval European settlements where diet was poor and disease demanded more energy of the immune system than average, so growth was sacrificed. If we look at pre-agricultural foraging populations, we often see relatively tall people. This is a bit enigmatic because so many modern forager groups are short statured. The explanation for that is probably that forager groups who are still around today, or have been extant over the last century or so, eek out their existence in relatively marginal habitats, the better parts of the landscape taken over by farmers and herders.

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See: “If this was the Stone Age, I’d be dead by now”
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So, we should expect that prehistoric lifespan varied across time and space, and as I noted, there were probably always elderly people, but just not too many of them, compared to today. It has become axiomatic to note in modern day conversations that many of our diseases, in the West, are “diseases of civilization.” This is a combination of health effects, but one of the most important is the lack of disease of the past because they have been addressed, at least for now, at least for a subset of the human population. Antibiotics alone probably allow a much larger proportion of the human population to survive long enough to experience age-related disease.

A good part of Howard’s documentary is about the science of aging. We want our scientists to figure out how to beat aging, or at least, slow it down. But this is not easy. Humans are primates, and primates are mammals. The very earliest mammals probably evolved to die young. That seems counterintuitive but it really isn’t. Life History Theory predicts that organisms will be selected to produce some sort of balance (or bias, imbalance) of three major energy shunting systems: growth, maintenance (including the immune system), and reproduction. Humans reproduce slowly, producing one (or two) offspring at a time, and putting a lot of effort into each one. This goes along with a long lifespan, because in order to produce a small number of high-quality offspring one must take some time. This, however, places additional demands on the immune system. In order to keep up with evolving microbes and the overall ravages of time, we need to spend a fair amount of effort on keeping from being too sick. And, we happen to be large, for a primate. That probably relates to predator pressure and a few other factors. So while we are selected to live a long time compared to the average primate (and certainly, the average mammal) we can only go just so far.

But perhaps more importantly, we (humans, and to a somewhat lesser extent, primates in general) are modified versions of mammals, and there are indications that mammals were never originally designed (by natural selection) to live long lives. Early mammals were probably small, and small goes along with a short lifespan in the mammalian world. Remember, those early mammals were living along side dinosaurs! (There were large early mammals but modern mammals, including all the more recent large one, probably evolved from a subset of them that were on the small side.) In a world where the smallest dinosaurs were larger than the largest mammals (or close to that) mammals were probably more often prey than predator. The best strategy if the most likely cause of death is being scarfed up by something larger is to live fast, have one or two litters of offspring, and do the whole “circle of life” thing really fast.

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See: How Long Is A Human Generation?
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One strong piece of evidence that a live fast and die young strategy applied to early mammals is the fact that mammal females are born already containing all the egg cells they will ever produce. This is the primary determinant of reproductive lifespan for human females. Organisms that are born ready to reproduce tend to have that strategy of rapid early reproduction followed by an early death. One of the more extreme examples of this is aphids. Aphids have two modes of reproduction, but in one of them, female aphids are born gravid. While human females are not born pregnant, they are born with the eggs ready to go.

Not only have humans (following the primate lead) extended their lifespan and slowed down their reproduction, but they ave added, apparently, another phase of life: Post reproductive. Human females in foraging societies around the world are productive members of their families after they have stopped being fertile. This seems to not make sense from a Darwinian perspective. Why not just keep reproducing until you die? Probably for two reasons. First, they can’t, because human lifespans are already extended to the limit of our phyolgeneticaly constrained abilities. Second, that post-reproductive period probably enhances Darwinian fitness. Studies have shown that elder women in foraging societies contribute significantly to the health and wellbeing of their own children’s offspring. Grandmothers are an adaptation!

When the unexpected appearance of a wild animal happens, there are usually one three factors at play. A migratory animal (typically a bird) is a bit off course, or lands where it normally flies over. The loon in the puddle by the gas station a couple of years ago, the rosette spoonbill up at the lake a few years ago, etc. A second reason, often used to explain moose in Massachusetts several years back, until it was realized that they were simply moving into the region, is disease. Some brain disease cause some mammals to wander aimlessly and that could result in the animal wandering far out of its range. The third reason which almost always applies, I think, to the occasional wolf or bear sighting ’round these parts, is dispersal. Without dispersal, nothing would be anywhere. Obviously. (Dispersal is linked to expansion of range, of course.)

And that, dispersal, is probably what is going on when a 3 meter long crocodile shows up at your barbecue in Queensland Australia. That, and of course, the steaks on the barbie which are irresistible to megafauna carnivores.

A team of researchers led by Craig Franklin, of the University of Queensland has been tracking crocodiles in the region for several years now. They discovered that smaller crocs don’t wander much, and the largest ones, those approaching five meters, don’t either. The small crocs are hiding out in good spots, and the larger ones are highly territorial, dominating a particular water hole. The in between size, mainly around 3 – 3.5 meters, are the the most nomadic. Some have traveled up to 1,000 kilometers over a year’s time, and up to 60 kilometers a day.

The team is now upgrading their equipment to include tracking devices that last longer.

You can observe the movements of some of their research subjects at the Franklin Eco-laboratory web site, here.

But seriously, Robert Martin, the famous primatologist, has an interesting piece in Psychology Today exploring this question. Go read it. I’ve got a few thoughts spurred by this research I’ll list briefly here.

First, it seems that wild primates give birth during their daily down-time, the period of time that they are generally inactive. Dirunal primates do so more at night, nocturnal primates do so more during the day. Various reasons have been proposed. I’ve not read the primary literature on this, but in my ignorance I wanted to propose a possible (maybe additional, maybe already covered) idea. It has been suggested that this is to avoid predation. It could also be the case that the down time itself happens when it does for the same reason, to avoid predation while resting. Consider just diurnal primates for a moment. Resting is probably a time that primates are more likely to be preyed on for one specific reason: they don’t have as many eyes scanning from as many angled over a large area. This would apply only to social primates, especially those that sometimes forage in multi-species groups. So, resting times would be times of lower vigilance, so those times are ideally placed during times when predators are less active. Nocturnal/crepuscular primates are least active during the part of the day that primates are less active, and diurnal primates that start to hunt in the morning may have fed by them.

I quickly add that this is a counterintuitive idea (the part about resting being placed during the low-risk time of the day). The assumption is usually that resting means you are quiet and hard to find, so less susceptible to predation. But the predators already know where the primates are, and can find them. Being more active may make primates more visible to other primates including human primatologists (arboreal monkeys can be hard to spot when they are just sitting there … usually you spot them when branches are swaying and calls are sounding). So it would be a tradeoff between increased vigilance associated with foraging (because you are out and about and observant), decreased vigilance associated with foraging (because you are busy stuffing your face with goodies), increase vigilance because you are resting (because you can sit there and look around without distraction) and decreased vigilance because you are resting (because you are zoning out and if you are hiding among thick vegetation have less of a view). Being a primate is complicated.

Like other diurnal primates, humans seem to give birth more at night. This is perhaps the baseline starting point for humans further developing a nocturnal active phase to their activities, which for a long time has been thought an important part of evolution. We social beings invent fire and this produces a sitting around the fire thing where we use language to do stuff. Sex too. Diurnal primates not only feed and move about during the day, but also have sex during the day, and in the open. The human pattern is to generally have sex at night, and more privately. This is what happens, perhaps, when you take a monogamous bird/gibbon-like mating system and deploy it in a highly social primate.

So the night time behavioral niche includes a number of activities, including sex, gossip, and popping out babies. All closely related things.

Anyway, go read Robert Martin’s article.

I’ve got to tell you that when I first saw the title of this book, the letters played in my head a bit. Tails of the Ex-Apes. That would be funny because apes don’t have tails. Or Tales of the Exapes. Pronounced as you wish. Perhaps in an Aztec accent.

Anyway…

Jon Marks is a colleague and a friend from way back. He is a biological anthropologist who has engaged in critical study of central biological themes, such as genetics, and he’s said a few things about race. He wears black, often does not shave, and has probably been a member of the Communist Party, or at least, taught a class or two on Marxist Theory. So, a book by Marks on “how we think about human evolution” (the subtitle) is not going to be about human evolution, but how we frame questions about human evolution, and how the process of unraveling answers to these questions revel our own biases. Dialectical stuff. Like that.

In the book Jon says interesting things about basic anthropological theory, thought, and key touchstone figures and topics like Darwin and kinship. On the more biological side of things, species, adaptations, gene trees, and phylogeny. The destructive core of the book is an anti-reductionist critique of evolutionary theory and the constructive core of the book is an bio-cultural argument as it applies to doing anthropology, as well as how it applies to the human (or just prehuman?) transformation to a self considering sort of sentient being that bothers to write books about the process of asking questions about itself. Humans are a product of lived experience, but not just that. Humanness is the product of the sum of human’s cultural history. And, actually, science, which is an important human thing, does not escape that framework, something I probably agree with (^^see the subtitle of my blog^^). Marks writes,

… we see the human species culturally. Science is a process of understanding, and we understand things culturally. We hope that we can observe and transcend the cultural biases of our predecessors, but there is no non-cultural knowledge. As a graphic example, consider the plaque that was attached to Pioneer 10 … Why was NASA sending pornography into outer space? … Because they wanted to depict the man and woman in a cultureless, natural state. But surely the shaves, haircuts, and bikini waxes are cultural! As are the gendered postures, with only the man looking you straight in the eye. In a baboon, that would be a threat display; let’s hope the aliens … aren’t like baboons.

And so on. Like that. Great book.

If you are teaching a course in human evolution, you might seriously consider using this as a second reading because of the critical treatment of material surely left unexamined by your textbook. Also, it would give the students a fairer sense of what they are in for if they chose Anthropology as a major, for better or worse. This is not introductory material, but the prose would work for any college student. Also, the text is well footnoted.

The book will be out any day now, scheduled for September. Available in various formats, very much worth the read.

This paper looks at neural imaging responses of subjects who observe, in photographs, various kinds of kissing. The two main variables are who is kissing (by gender) and the nature of the kiss.

One of the authors is my friend and colleague, Sheril Kirshenbaum. She wrote the book on kissing. No, seriously, she wrote this book, which I’ve reviewed here.

From the abstract of the paper:

With a few exceptions, the literature on face recognition and its neural basis derives from the presentation of single faces. However, in many ecologically typical situations, we see more than one face, in different communicative contexts. … Although there is no obvious taxonomy of kissing, we kiss in various interpersonal situations (greeting, ceremony, sex), with different goals and partners. Here, we assess the visual cortical responses elicited by viewing different couples kissing with different intents. The study thus lies at the nexus of face recognition, action recognition, and social neuroscience. Magnetoencephalography data were recorded from nine participants in a passive viewing paradigm. We presented images of couples kissing, with the images differing along two dimensions, kiss type and couple type. We quantified event-related field amplitudes and latencies. In each participant, the canonical sequence of event-related fields was observed, including an M100, an M170, and a later M400 response. The earliest two responses were significantly modulated in latency (M100) or amplitude (M170) by the sex composition of the images (with male-male and female-female pairings yielding faster latency M100 and larger amplitude M170 responses). In contrast, kiss type showed no modulation of any brain response. The early cortical-evoked fields that we typically associate with the presentation and analysis of single faces are differentially sensitive to complex social and action information in face pairs that are kissing. The early responses, typically associated with perceptual analysis, exhibit a consistent grouping and suggest a high and rapid sensitivity to the composition of the kissing pairs.

Interesting research, part of the bigger picture of how human perception operates in an important social context. I asked Shiril Kirshenbaum for a quick comment and she told me that one of the most interesting parts of this work is “that usually we think of science writing as something that happens after research or discovery. But here we have a nice example demonstrating that the relationship can go both ways where new science has been driven by the storytelling.”

A kiss is not a kiss: visually evoked neuromagnetic fields reveal differential sensitivities to brief presentations of kissing couples. 2015. Cogan, Gregory, Sheril Kirshenbaum, Jeffry Walker, and David Poeppel. NeuroReport, August 18, 2015.

Now, researchers have demonstrated cross-species response to distress calls by young. They recorded distress calls by various mammals such as seals, dogs, cats, and humans. Never mind how they got the distress calls. Anyway, they played these for White Tailed Deer females and got a response. The mother deer moved towards the recordings. These baby mammals all have similar pitched calls. The researchers also recorded bats and lowered the pitch to be within that range, and the deer responded to this as well.

Presumably there is strong selection on responding to distress calls of young, but not strong selection on being selective, probably because the circumstances do not arise that often.

More here.

James J. “Whitey” Bulger, the notorious Boston gangster who rampaged through the city’s underworld for decades before slipping away from authorities and eluding a worldwide manhunt for more than 16 years, was convicted today in federal court of charges that will likely keep him in prison for the rest of his life.

Don’t count on that. Whitey has slipped from the clutches of justice several times before. He’ll probably make a break for it between the court house and the jail, and if not, he’ll break out by pretending to be laundry or something in a few weeks.

Anyway, I started making references to Whitey Bulger back when he was just … retiring … and I live in the Boston Area, because he provided me with a good analogy in teaching about behavioral biology. So, whenever Uncle Whitey gets in the news I like to repost that. So …. from an earlier post (which still refers to him as a fugitive) we have this ….

This may or may not be a recent photograph of fugitive Whitey (James) Bulger of Boston’s Winter Hill Gang. Most of you won’t know who Whitey Bulger is. He is actually on the FBI’s ten most wanted list. He may have been spotted in Italy last Spring, and the FBI is just now asking for assistance from anyone who knows where he might be. (That’s not gonna work.)

Whitey was top dog in Boston’s Winter Hill gang. His brother was a Senator for the Commwealth of Massachusetts, and served as Senate President for several years.

It is said that Whitey was an FBI informant, and that his handler, FBI Special Agent John Connolly, tipped Whitey off that he was about to be indicted on racketeering charges. No problem. Whitey had left stashes of cash in safe deposit boxes all around the world, in preparation for the day he had to go on the lam. So he took off in 1995, and the FBI has not been able to catch up. Special Agent Connolly is pulling a ten year vacation in the stir.

I remember when Whitey disappeared, and ever since then, I’ve used him almost annually in lecture material describing the Trivers-Willard hypothesis. It goes like this:

This may or may not be a recent photograph of Robert Trivers, of the Trivers-Willard Hypothesis. The Trivers-Willard model (I prefer to call it a “model” rather than a “hypothesis” because it is not specific enough to really be a hypothesis … it’s a model that generates lots of hypotheses) states that selection should favor the ability to differentially bias investment in offspring by sex if the two sexes have differential variances in reproductive success, and if there is any way to predict offspring rank. That’s a bit thick, so it requires some examples and further explanation. Maybe a story about a mobster would help..

OK, so an example: Red deer (also known as Elk) give birth to one offspring (max) per year. Males compete for access to or to be chosen by females. So, only a small percentage of male red deer mate in a given year, a significant percentage may never mate at all, and a very small percentage sire many many little red deer. Male red deer have a high variance in reproductive success. If you tried to predict how many offspring a given randomly chosen male would have, knowing nothing at all, your best guess would be the average number of offspring red deer have in an average lifetime. But you would be wrong almost every time because the actual number is highly variable. Male red deer have high variance in RS.

Females, on the other hand, have a pretty standard number of offspring. There is not much competition among them, they can always find a male to mate with, etc. If you needed to guess how many offspring a particular randomly chosen female red deer would have in a life time, you could guess the average, and you would be right on or very close. Female red deer have low variance in RS.

So, male and female red deer have differential variance in RS. Males high, females low.

If a female red deer could somehow “predict” the likelihood of her offspring getting to mate, i.e., if she could tell if any offspring she had in the present year (male or female) would be average vs. high ranking, then selection should favor the evolution of a mechanism to actually give birth to the appropriate sex offspring (thus biasing investment in one sex or the other). It turns out that she can. A female red deer that is herself average or lower-quality (thin, ill, injured) is likely to give birth to an offspring that will be either low ranking or average. But if the mother-to-be red deer is high ranking, she is likely to give birth to an individual who will grow up to be high ranking.

Under these conditions, she should have a female offspring if she’s average or low ranking, but a male if she’s high ranking. And that, it turns out, is what red deer actually do.

That should be clear. But in case it isn’t, let’s take it down do real life, and bring in the gangsters.

You check the mail this afternoon, and there is a letter from a law firm you have never heard of. It says that your Great Aunt Tillie (whom you’ve also never heard of) just died, and left you with $1,000 in her will. The check is enclosed.

This may or may not be a recent photograph of a male red deer. Holy crap. Found money! What are you going to do with it? So you and your close advisors (your roommates, your cat, etc.) discuss it and you narrow it down to two choices. Choice A and Choice B.

Choice A is to go to your broker and buy $1000 worth of a nice, relatively safe mutual fund. The fund will buy and sell reliable blue chip stocks, thus spreading the risk over several companies, and over time you can expect to get a return of 50 bucks a years, easy.

Choice B is to buy 1000 one dollar lottery tickets. Your chances of winning are slim, but if you do, you will win 87 million dollars.

So, what do you do? The obvious sane choice is to buy the mutual fund.

But what if your cousin is Whitey Bulger? Whitey Bulger, as head of the Winter Hill Gang, is said to have owned the director of the Commonwealth Lottery agency.The connection between Whitey Bulger and the Lottery has never been proven. They don’t have a shred of evidence. He was, however, indicted for 21 counts of RICO-Murder. It is said that one of the things that tipped off authorities about this is that some of his relatives were winning the lottery a little more often than they should have. So, say your cousin is Whitey Bulger, and last time you saw him (at a family wedding) he told you … “hey, if you ever want to take a “chance” on the lottery, let me know … I can make that work for you…”

So now, you have two choices.

Choice A: Invest in a mutual fund and gain a return of 50 bucks a year (that’s dollars, not elk); and

Choice B: Buy 1000 PowerBall tickets and have a great deal of certainty of winning 87 million dollars.

What would you do?

In case it isn’t already clear. the baby male elk is a lottery ticket, the baby female elk is a mutual fund, but the female can guess pretty accurately if the lotter ticket (male offspring) will pay off. Because the elk’s cousin is Whitey Bulger. See?

Here is one of the nicest demonstrations of the relationship between parasite load and reproduction that I’ve seen in a while. And, as is so often the case, we gain valuable knowledge by closely observing great tits.

Photo Credit: OneTrack via Compfight cc