Category Archives: Artiodactyla

Bovids Of The World

According to the Encyclopedia Britannica, there are 143 species of bovids. The Animal Diversity Web is a bit less precise, indicating that there are “more than 140 extant and 300 extinct species.” That second number is highly questionable because today there exist sister species that are so similar I doubt they could be told apart from fossils alone. If you check around the internet, this ~140 number comes up again and again, and Wikipedia says 143.

horns640hResearch published in 2011 and later by Colin Groves, Peter Grubb, and David Leslie, which has been tagged as controversial by some but accepted by others, puts this number much higher, over 270. Why such a difference, and why is this controversy only emerging recently? It isn’t like bovids are barely studied, or highly cryptic.

One of the reasons probably has to do with vagueness in the species concept itself, and it may well be the case that there are sets of species defined by Groves et al that are too finely split. But, the most likely explanation is that more modern methods, using DNA and recently developed statistical techniques, simply come up with a larger number. I’ve only read some of this literature, but I’m pretty sure the larger number is much closer to correct than the smaller number.

This has an important impact on understanding and addressing problems of ecology, diversity, evolution, and conservation. With respect to conservation, this means that some populations of bovids, the more rare and geographically restricted ones, are likely to be more at risk of extinction, if there are other populations at different locations that can no longer be referenced as survivors. It has been suggested, indeed, that splitting large taxonomic groups into larger numbers of species is some kind of pro conservation shenanigans. Such hippie-punching has no place in modern biology, of course. The increase in our accounted-for diversity that happens with more research is both expected from historical trends over recent decades (though it is a reverse of earlier decreases in diversity as more was learned about certain groups) and is predicted by evolutionary theory.

Screen Shot 2016-04-13 at 3.00.19 PMAnyway, I’m not here to talk about that controversy exactly. Rather, I want to point you do a new book, a really fantastic book, called Bovids of the World: Antelopes, Gazelles, Cattle, Goats, Sheep, and Relatives, by José Castelló.

Castelló uses the larger number, by the way: 271. And this book includes all of them.

The majority of this 664 page book consists of plates and a species description on the left, and details on the right, including excellent range maps, with one species in each layout. The species are divided by the usual commonly accepted tribes. This also means that many but not all of the species are grouped by very large geographical regions, because that is how the bovids are organized across our global landscape.

The back matter consists of nothing more than an index, critical in such a volume, and the front matter has an overview of what a bovid is, and details about key anatomy used in the field guide.

This book is one of a handful in the emerging subcategory of animal books that covers an entire taxonomic group either globally or nearly globally. I recently reviewed Waterfowl of North America, Europe and Asia by Reeber, which isn’t quite global but since waterfowl tend to migrate is nearly so. A while back I reviewed the guide “Sharks of the World” by Compagno, Dando, and Fowler. And I’ve reviewed one of my favorite guides of all time, “Carnivores of the World“, which covers all the carnivores except those that evolved partly into fish.

pantelope640hThis category of book is not meant to be the one book you carry with you while touring around in the field. If you go to Africa, bring The Kingdon Field Guide to African Mammals (it includes the bovids), for example. Rather, this book is to understand the bovids as a major and important taxonomic group.

Paging through a given tribe’s entries, you can come to understand biogeography better, as you see the ranges depicted on the maps of a continent or region. Also, small bovids tend to have smaller geographical ranges than larger bovids, but there are major exceptions. Why those exceptions?

Looking at the physical variation in key features, such as body size, sexual dimorphism, head dress, and markings, you can see patterns that are best explained with interesting evolutionary and ecological theories. If you teach behavioral biology or zoology, this will be a useful reference point for your thinking on all those key bovid examples. Or, if you are just interested in animals, or are planning a trip to a place where you’ll be observing antelopes or other bovids, you may want to invest in this.

And when your crotchety Uncle Bob is over for a holiday dinner and you get into an argument about how many duikers there are in West Africa vs. Central Africa, you can pull out your copy of Bovids of the World and settle the bet!

The plates are drawings, not photographs, which is entirely appropriate in this sort of book. Habitats matter to photographs and that would bias the physical comparisons. Also, I can tell you from personal experience that many of the bovids, especially the forest dwellers, just don’t have great photographs anyway.

I studied the information on the bovids with which I’m familiar from my own fieldwork, and I see only quality information.

As far as I know, there is not another guide like this available. Also it is not that expensive.

Table of Contents:
FOREWORD by Brent Huffman and Colin Groves 5
Impalas 24
Sunis, Royal Antelope, Pygmy Antelope 28
Reedbucks, Waterbucks, Rhebok 38
Gazelles, Oribis, Steenbok, Grysbok, Dik-diks 82
Klipspringers 224
Duikers 244
Sheep, Goats, and relatives 302
Horse Antelopes 466
Tsessebes, Topis, Hartebeests, Wildebeests 496
Nilgai, Four-horned Antelope 542
Spiral-horned Antelopes 546
Bison, Buffaloes, Cattle, Saola 596

Are Pigs Really Like People?

We hear this all the time. Pig physiology is like people physiology. Pigs and humans have the same immune system, same digestive system, get the same diseases. Pigs are smart like people are smart. Pigs are smarter than dogs. And so on. Ask a faunal expert in archaeology or a human paleoanatomist: Pig teeth are notoriously like human teeth, when fragmented. Chances are most of these alleged similarities are overstated, or are simply because we are all mammals. Some are because we happen to have similar diets (see below). None of these similarities occur because of a shared common ancestor or because we are related to pigs evolutionarily, though there are people who claim that humans are actually chimpanzee-pig hybrids. We aren’t.

But what if it is true that pigs and humans ended up being very similar in a lot of ways? What if many of the traits we attribute to our own species, but that are rare among non-human animals, are found in pigs? Well, before addressing that question, it is appropriate to find out if the underlying assumption has any merit at all. A new study by Lori Marino and Christina Colvin, “Thinking Pigs: A Comparative Review of Cognition, Emotion, and Personality in Sus domesticus,” published in the International Journal of Comparative Psychology, provides a starting point.

There are two things you need to know about this study. First, it is a review, looking at a large number of prior studies of pigs. It is not new research and it is not a critical meta-study of the type we usually see in health sciences. The various studies reviewed are not uniformly evaluated and there is no attempt at assessing the likelihood that any particular result is valid. That is not the intent of the study, which is why it is called a review and not a meta-study, I assume. But such reviews have value because they put a wide range of literature in one place which forms a starting point for other research. The second thing you need to know is that the authors are heavily invested in what we loosely call “animal rights,” as members of the Kimmela Center for Animal Advocacy and the Someone Project (Farm Sanctuary). From this we can guess that a paper that seems to show pigs-human similarities would ultimately be used for advocating for better treatment for domestic pigs, which are raised almost entirely for meat. There is nothing wrong with that, but it should be noted.

In a moment I’ll run down the interesting findings on pig behavior, but first I want to outline the larger context of what such results may mean. The paper itself does not make an interpretive error about pig behavior and cognition, but there is a quote in the press release that I’m afraid will lead to such an error, and I want to address this. The quote from the press release is:

Dr. Marino explains that “We have shown that pigs share a number of cognitive capacities with other highly intelligent species such as dogs, chimpanzees, elephants, dolphins, and even humans. There is good scientific evidence to suggest we need to rethink our overall relationship to them.”

What does that mean? In particular, what does the word “relationship” mean? In a behavioral comparative study, “relationship” almost always refers to the evolutionary structure of the traits being observed. For example, consider the question of self awareness, as often tested with the Gallup Test, which measures Mirror Self Recognition (MSR). If a sufficient sample of test animals, when looking in a mirror almost always perceive a conspecific, then that species is considered to not have MSR. If most, or even many, individuals see themselves, then that species is said to have MSR, a kind of self awareness that is linked to a number of important other cognitive capacities.

Humans have MSR. So, do our nearest relatives, the chimps have it? Do the other apes have it? Other primates? Is this a general mammalian capacity or is it a special-snowflake trait of our own species? It turns out that all the great apes have MSR, but primates generally do not. It may or may not appear among other primates (mostly not). So MSR reflects something that evolved, likely, in the common ancestor of humans and all the other apes. So, the relationship among the primates with respect to MSR, phylogenetically, is that MSR is a shared derived trait of the living apes, having evolved in or prior to that clade’s last common ancestor.

But we also see MSR in other species including, for example, elephants. The presents of MSR in elephants does not mean MSR is a widespread trait that humans and elephants both have because a common ancestor hat it. Rather, in some cases (the great apes), MSR is clustered in a set of closely related species because it evolved in their ancestor, and at the same time, it appears here and there among other species for either similar reasons, or perhaps even for different reasons.

This is why the word “relationship” is so important in this kind of research.

It is clear that Dr. Marino does not use the word “relationship” in that press release to mean that pigs and humans share interesting cognitive and behavioral traits because of common ancestry, but rather, I assume, the implication is that we may want to think harder about how we treat pigs because they are a bit like us.

One could argue, of course, that a species that is a lot like us for reasons other than shared evolutionary history is a bit spooky. Uncanny valley spooky. Or, one could argue that such a species is amazing and wonderful, because we humans know we are amazing and wonderful so they should be too. Indeed one could argue, as I have elsewhere, that similarity due to shared ancestry and similarity due to evolutionary convergence are separate and distinct factors in how we ultimately define our relationship to other species, how we treat them, what we do or not do with them. The important thing here, that I want to emphasize, is that human-pig similarity is not the same thing as human-chimp similarity. Both are important but they are different and should not be conflated. I honestly don’t think the paper’s authors are conflating them, but I guarantee that if this paper gets picked up by the press, conflation will happen. I’ll come back to a related topic at the end of this essay.

I’ve been interested in pigs for a long time. I’ve had a lot of interactions with wild pigs while working in Africa, both on the savanna and the rain forest. One of the more cosmopolitain species, an outlier because it is a large animal, is the bush pig. Bush pigs live in very arid environments as well as the deepest and darkest rain forests. There are more specialized pigs as well. The forest pig lives pretty much only in the forest, and the warthog does not, preferring savanna and somewhat dry habitats. Among the African species, the bush pig is most like the presumed wild form of the domestic pig, which for its part lived across a very large geographical area (Eurasia) and in a wide range of habitats. I would not be surprised if their populations overlapped at some times in the past. This is interesting because it is very likely that some of the traits reviewed by Marino and Colvin allow wild pigs to live in such a wide range of habitats. There are not many large animals that have such a cosmopolitain distribution. Pigs, elephants, humans, a few others. Things that know something about mirrors. Coincidence? Probably not.

Pigs (Sus domesticus and its wild form) have an interesting cultural history in the west. During more ancient times, i.e., the Greek and Roman classical ages, pigs were probably very commonly raised and incorporated in high culture. One of Hercules seven challenges was to mess with a giant boar. Pigs are represented in ancient art and iconography as noble, or important, and generally, with the same level of importance as cattle.

Then something went off for the pigs. Today, two of the major Abrahamic religions view pigs as “unclean.” Ironically, this cultural insult is good for the pigs, because it also takes them right off the menu. In modern Western culture, most pigs are viewed as muddy, dirty, squealing, less than desirable forms. Bad guys are often depicted as pigs. One in three pigs don’t understand their main predator, the wolf. There are important rare exceptions but they are striking because they are exceptions. This denigration of pigs in the West is not found globally, and in Asia pigs have always been cool, sometimes revered, always consumed.

I should note that I learned a lot of this stuff about pigs working with my good fiend and former student Melanie Fillios, who did her thesis (published here) on complexity in Bronze Age Greece, and that involved looking at the role of pigs in the urban and rural economies. At that time Melanie and I looked at the comparative behavioral and physical biology of cattle vs. pigs. This turns out to be very interesting. If you started out with a two thousand pounds of pig and two thousand pounds of cattle, and raised them as fast as you could to increase herd size, in a decade you would have a large herd of cattle, but if you had been raising pigs, you’d have enough pigs to cover the earth in a layer of them nine miles thick. OK, honesty, I just made those numbers up, but you get the idea; Pigs can reproduce more than once a year, have large litters, come to maturity very quickly, and grow really fast. Cattle don’t reproduce as fast, grow slower, take longer to reach maturity, and have only one calf at a time.

On the other hand, if you have cattle, you also have, potentially, milk (and all that provides), hoof and horn (important in ancient economies) and maybe better quality leather. I’ll add this for completeness: Goats are basically small cows with respect to these parameters.

Now, having said all that, I’ll summarize the material in the paper so you can learn how amazing pigs are. From the press release:

  • have excellent long-term memories;
  • are whizzes with mazes and other tests requiring location of desired objects;
  • can comprehend a simple symbolic language and can learn complex combinations of symbols for actions and objects;
  • love to play and engage in mock fighting with each other, similar to play in dogs and other mammals;
  • live in complex social communities where they keep track of individuals and learn from one another;
  • cooperate with one another and show signs of Machiavellian intelligence such as perspective-taking and tactical deception;
  • can manipulate a joystick to move an on-screen cursor, a capacity they share with chimpanzees;
  • can use a mirror to find hidden food;
  • exhibit a form of empathy when witnessing the same emotion in another individual.
  • Pigs are very snout oriented. They have lots of nerve endings in their snouts and can use the information they get from this tactile organ for social interactions and finding food. They can tell things apart very easily, learn new classifications, and remember objects and things about them. This makes sense for an animal that forages at the ground surface, including underground, for a very wide range of food types.

    One of the cool human traits we often look for in other animals is the ability to time travel. We don’t actually travel in time, but in our minds, we can put ourselves in other places and other times, and run scenarios. Some of the basic capacities required to do this include a sense of lengths of times for future events or situations, and an understanding of these differences. Pigs can learn that of two enclosures they can choose from, one will let them out sooner than the other one, for example.

    Pigs have excellent spatial memory and can learn where things are and how to find them. They can do mazes as well as other animals that have been tested in this area.

    Pigs have individual personalities, to a large degree, and can discriminate among other individuals and recognize certain aspects of their mental state. This applies to other individual pigs as well as individuals of other species (like humans).

    Pigs have a certain degree of Machiavellian intelligence. This is rare in the non-human animal world. If a pig has the foraging pattern for a given area down well, and a potential competitor pig is introduced, the knowledgable pig will play dumb about finding food. They don’t have MSR but they can use mirrors to find food.

    Now, back to the evolutionary context. I’ve already hinted about this a few times. Pigs and humans share their cosmopolitain distribution, with large geographic ranges and a diversity of habitats. We also share a diverse diet. But, it goes beyond that, and you probably know that I’ve argued this before. Pigs are root eaters, as are humans, and this feature of our diet is probably key in our evolutionary history. From my paper, with Richard Wrangham, on this topic:

    We propose that a key change in the evolution of hominids from the last common ancestor shared with chimpanzees was the substitution of plant underground storage organs (USOs) for herbaceous vegetation as fallback foods. Four kinds of evidence support this hypothesis: (1) dental and masticatory adaptations of hominids in comparison with the African apes; (2) changes in australopith dentition in the fossil record; (3) paleoecological evidence for the expansion of USO-rich habitats in the late Miocene; and (4) the co-occurrence of hominid fossils with root-eating rodents. We suggest that some of the patterning in the early hominid fossil record, such as the existence of gracile and robust australopiths, may be understood in reference to this adaptive shift in the use of fallback foods. Our hypothesis implicates fallback foods as a critical limiting factor with far-reaching evolutionary e?ects. This complements the more common focus on adaptations to preferred foods, such as fruit and meat, in hominid evolution.

    Pigs and humans actually share dental and chewing adaptations adapted, in part, for root eating. The pig’s snout and the human’s digging stick have been suggested (see the paper) as parallelisms. And so on.

    Yes, humans and pigs share an interesting evolutionary relationship, with many of our traits being held in common. But this is not because of shared ancestry, but rather, because of similar adaptive change, independent, in our evolutionary history. This whole root eating thing arose because of a global shift from forests to mixed woodland and otherwise open habitats, which in turn encouraged the evolution of underground storage organs among many species of plants, which in turn caused the rise of a number of above ground root eaters, animals that live above the surface but dig. Not many, but some. Pigs, us, and a few others.

    That does not make us kin, but it does make us kindred.

    Caribou Cam Proves Reindeer Are Real

    Every now and then, more often than you might expect, I mention something in lecture (usually in a classroom in front of students) and a small number of individuals express incredulity that the thing exists. Pygmies are one of those terms that garners disbelief. Many people assume they are made up. At the same time, a disconcerting number of times the opposite happens. Mermaids, aliens, dragons, Atlantis, etc. are not real but many students, educated by the History and Discovery channels, apparently, (I don’t watch them but I hear things), think they are.

    Strangely, one of the things that people often think to be fiction is the venerable Reindeer. The first part of this confusion may be that we use two words for them: Reindeer and Caribou. Also, since Caribou is now a kind of coffee shop, there may be additional confusion.

    Anyway, reindeer are real, and caribou too. And, the Como Zoo in Saint Paul, Minnesota has set up a web cam that lets you watch some of the deer (caribou is kind of deer, of which there are many) live. They don’t do a lot, but they are cute.

    Click here to watch the Reindeer Cam, which really should be called the Caribou Cam but maybe they tried to use that term but got sued by some coffee shop, I don’t know.

    Keep an eye on the prey: You’ll find the predator

    In Robert Gardner’s documentary film Dead Birds, the men of a highland New Guinea village guard the perimeter of the territory, watchful for men of the neighboring group who may be intent on sneaking into the gardens to capture and kill an unwitting child or woman in order to avenge a prior death. But they don’t see the men sneaking through the dense riparian forest. They don’t even look for them. Rather, they see the birds fly from their preferred habitat where they are foraging or resting, startled into the open by … something. The birds belie the predator.
    Continue reading Keep an eye on the prey: You’ll find the predator

    The African Buffalo

    i-1f5e45f094e922e9955cc2356ff60451-BuffaloFish.jpgThe African Buffalo is NOT a bison, and it is NOT a “water buffalo” (it is not even the same genus as water buffalo). But like these other beasts, it is a kind of cattle.The scientific name of the African Buffalo, or Cape Buffalo, is Syncerus caffir. Only the most cynical taxonomists would support the continued use of this term. “Caffer” is the same word as “Kaffir” which in modern usage has the same connotation as “Nigger.” The term “caffir” or “kaffir” has been dropped from other species names, but as far as I know, not yet from the Cape Buffalo. I don’t know why.This particular buffalo is standing tummy-deep in the mud at the base of a fairly large dam on a river in Kruger National Park, South Africa. You can obviously see that the dam (lake) is somewhat dried up. The disturbed surface of the water that you can see off to the right of the Cape Buffalo is caused by very large cat fish who are waiting for rain. Continue reading The African Buffalo

    Topi or not Topi …

    Blogging on Peer-Reviewed ResearchGo to any bar and you’ll see a lot of males standing and sitting around not mating. I’ll bet you would have guessed that the reason they are not mating is that no females will mate with them for one reason or another. But there is the distinct possibility that they are very inconspicuously resisting mating opportunities. It turns out that males can do this …. avoid mating without conspicuous resistance … more easily than females. For obvious reasons.This could be why what has become (inappropriately) known as “reversed sexual aggression” often goes unnoticed, and a recent study of the African antelope Damaliscus lunatus (a.k.a. “topi”) explores this possibility. Continue reading Topi or not Topi …