From the category archives:

Theme Weeks

Primorye Week: Siberian Musk Deer (Moschus moschiferus)

by JR Kinyak on September 26, 2011

in Theme Weeks,Ungulates

Siberian musk deer (click image to enlarge)


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I’m reading a book called The Tiger: A True Story of Vengeance and Survival, by John Vaillant. It’s about Siberian tigers and tiger trackers in the far east of Russia, a region called Primorsky Krai, the Maritime Province, or Primorye. It’s a fascinating place, closer geographically to Beijing and even to Australia than to Moscow, and amazingly biologically diverse. Vaillant says that “Primorye is also the meeting place of four distinct bioregions,” the taiga, the steppes, the subtropics, and the far-northern forest:

“Here, timber wolves and reindeer share terrain with spoonbills and poisonous snakes, and twenty-five-pound Eurasian vultures will compete for carrion with saber-beaked jungle crows. Birch, spruce, oak, and fir can grow in the same valley as wild kiwis, giant lotus, and sixty-foot lilacs, while pine trees bearing edible nuts may be hung with wild grapes and magnolia vines. These, in turn, feed and shelter herds of wild boar and families of musk deer whose four-inch fangs give them the appearance of evolutionary outtakes. Nowhere else can a wolverine, brown bear, or moose drink from the same river as a leopard, in a watershed that also hosts cork trees, bamboo, and solitary yews that predate the Orthodox Church. In the midst of this, Himalayan black bears build haphazard platforms in wild cherry trees that seem to fragile for the task, opium poppies nod in the sun, and ginseng keeps its secret in dappled shade.”

Beautiful, isn’t it? And inspiring to an amateur mammalogist like me. This week, we’ll look at some of the mammals of Primorye, like those mentioned above, beginning with today’s fellow, who isn’t Bunnicula, but rather the Siberian musk deer.

Musk deer, as their name suggests, are the traditional source of the musk that we use in perfume. Musk comes from a gland, or musk-pod, in the male musk deer, and generally, someone who wants that musk-pod will kill the deer for it. The musk deer has been so heavily hunted that it is now internationally protected, but still, poachers poach, and our friend’s numbers are declining.

Here is a link to a video from Arkive of the musk deer in action. It has powerful hind legs and weaker front ones, like a rabbit, and it moves through a series of bounds. I also like the sound of the cold wind in this video.
ARKive video - Siberian musk deer - overview

Tagged as: books, deer, humans, threats

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Random Week: Gregarious Short-tailed Rat (Brachyuromys ramirohitra)

by JR Kinyak on April 14, 2011

in Rodents,Theme Weeks

Gregarious short-tailed rat (click image to enlarge)


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This week, I’m drawing mammals selected randomly by random.org. Each day, it’s a surprise to me, and this should be a good way to get through some of the mammals that I would be unlikely to choose on my own…like this one, the gregarious short-tailed rat. Nothing against him, but there’s very little information available about him and very few photographs for reference, and those are the ones I usually put off in the hopes that somebody will have taken pictures of them by the time I get around to them again. But picking them randomly doesn’t allow for that. And I have to tell you, it’s satisfying to draw one of the obscure guys, one where I have to really dig to find even a reliable description. It’s a job-well-done, wiping-my-hands-with-pleasure kind of feeling.

So, here is the gregarious short-tailed rat. He looks friendly enough, doesn’t he? These rats are endemic to eastern Madagascar, where they live in forests and fields, making grassy tunnels and evading capture.

Tagged as: random, rat

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Random Week: Inland Forest Bat (Vespadelus baverstocki)

by JR Kinyak on April 13, 2011

in Bats,Theme Weeks

Inland forest bat (click image to enlarge)


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I had fun with the random rodents I drew the other day, so I’ve decided on a new theme week: Random Week! I put all the mammals I haven’t yet drawn in random.org’s list randomizer and for the next week-ish, I’ll be as surprised as you by what mammal I draw each day. (I only put in their genus and species names, not families or orders, so I’m more likely to be in the dark until I look them up.)

Today’s randomly selected mammal is an Australian bat, the inland forest bat, whose scientific name comes from a still-living zoologist, Peter R. Baverstock, who was born in 1948. I think this is my first mammal named for a baby boomer! Well, the first that I’ve noticed was named for a baby boomer. (Did they have a baby boom in the ’40s and ’50s in Australia?)

The inland forest bat is very small, weighing 3 to 7 grams, or 3 to 7 paper clips (thanks to Mrs. Beard, my third grade teacher, for that helpful comparison I’ve used my whole life). It lives throughout Australia in dry areas, roosting in hollow trees or abandoned buildings.

Tagged as: names, random

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Mating Week: Saddleback Tamarin (Saguinus fuscicollis)

by JR Kinyak on March 5, 2011

in Primates,Theme Weeks

Saddleback tamarin (click image to enlarge)


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I’ve decided to go ahead and call this an official theme week. This is the fifth and last entry in our Daily Mammal Mating Week. The saddleback tamarin, which lives in Bolivia, Brazil, Colombia, Ecuador, and Peru, practices polyandry, which means that a single female mates with more than one male. (Polygamy technically refers to a marriage or partnership with more than two partners; polygyny means one male and two or more females. Other members of this tamarin’s taxonomic family also practice polyandry.)

A typical group of tamarins includes one mating female and at least two males, but they’re flexible about their family systems, and sometimes they’re in a monogamous pair accompanied by adolescent offspring or in a group that includes other, non-dominant females, whose ovulation is suppressed and who help take care of the dominant female’s babies, who are nearly always born in sets of twins. All the males take turns mating with the dominant female, and Walker’s Mammals of the World says that “tamarins generally display minimal intragroup aggression, with a marked degree of cooperation and tolerance, even by sexually active males towards one another.” It’s a nice system:

In Saguinus the father and sometimes other adult members of a group assist at birth, receiving and washing the young. The newborn have a coat of short hair and are helpless. They cling tightly with their hands and feet to the body of the mother or father. The father transfers the young to the mother at feeding time and then accepts them from the mother again after feeding…Several members of a group besides the mother and father may help carry and provision the young…

So that’s it for our Mating Week. In addition to today’s polyandrous group, we’ve visited a lek, a barbaric “rape society,” a monogamous pair, and a “big-bang” reproducer. We mammals find what works, and the diversity in that is pretty beautiful.

Tagged as: mating, monkey

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Mating Week: Brown Antechinus (Antechinus stuartii)

by JR Kinyak on March 4, 2011

in Marsupials,Theme Weeks

Brown antechinus (click image to enlarge)


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Every female wants a good father for her babies. Every male wants a good mother for his babies. That’s what life is all about. The more I study other animals, the more I think the meaning of life is: have sex and have babies, and have sex and babies with a mate or mates of good quality. Is there any other reason that anyone does anything?

But different species have different ways of finding the best mates, and within a species, the two sexes have different methods, too. In most mammals, the males aren’t choosy. They just impregnate everyone they can, and hope that their promiscuity will mean the odds are in favor of their finding at least one good mother for their offspring. Most mammalian females are pickier because they have such a large investment in raising the babies, from gestation to nursing and weaning and carrying their young around on their backs as they swing through the treetops. They can’t produce as many offspring, so they have to make sure the ones they have are good ones. Sometimes this means they look for the male who is best at fighting off other males, or they look for the one who can defend them against predators. Sometimes they look for the one with the most attractive pheromones and the prettiest honking noise, like in yesterday’s Gambian epauletted bat.

Females of the brown antechinus species, a mouselike Australian marsupial, look for the males with the strongest sperm. At least in this species, strong sperm means strong babies—babies who survive infancy, anyway. How do they find the best sperm? They mate with everyone who crosses their path and let the sperm fight it out. A typical brown antechinus litter includes the babies of three or four fathers, and studies have shown that the antechinus fathers who sire the most offspring also sire the strongest offspring—the offspring with the best chance of survival. In the end, according to this 2006 Scientific American article about the brown antechinus, this has the same result as mating with just one really good male.

Some of the males don’t end up actually passing on any of their genes, even though they mate just as much as the others. But they don’t care because they’re dead. You see, the brown antechinus mating system is what’s actually referred to as big-bang reproduction. They engage in two weeks of nonstop sex, some sessions lasting 12 hours or so, and then their poor little systems just give out. The stress of all that mating causes the males to suffer immune suppression and infection and internal bleeding and they all die before their first birthday. The ones with the strongest sperm father babies that will be born after their dads are gone, and the ones with weak sperm die in vain. The females survive long enough to give birth and nurse and wean, but they don’t live much longer than a year themselves. Then the next generation repeats the whole thing the following fall, and so it goes on and on and on.

Coco (age 12) drew a brown antechinus, too:

Brown antechinus by Coco (click image to enlarge)

Tagged as: coco, mating

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Mating Week: Gambian Epauletted Bat (Epomophorus gambianus)

by JR Kinyak on March 3, 2011

in Bats,Theme Weeks

Gambian epauletted bat (click image to enlarge)


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Last June, I drew the hammer-headed fruit bat, which is known for its lek mating system. The Gambian epauletted bat, today’s mammal, uses a similar lek system. In Courtship in the Animal Kingdom, Mark Jerome Walters explains leks:

In some animals, however, males offer neither defense of the females nor any particular resource. There is no trade-off of riches, nor any guarantee that the male will help raise the offspring. Such males gather merely to display themselves. The group display is known as a “lek”—a word thought to have come from the Swedish for “sport” or “play”—and the tree, pasture, or other area where they display is known as an “arena.”

According to Walters, male Gambian epauletted bats “gather at dusk, inflate elastic cheek pouches, and emit a singsong honking sound audible for 200 yards or more. The male then unfurls tufts of white hair from pockets on each shoulder—hence the name. These epaulets are thought to contain pheromones. Wafted off into the twilight by the male’s gently flapping wings, they may help to attract a female.”

How neat, isn’t it? They have pockets on their shoulders, from which they unfurl tufts of hair, and then flap their wings to send their pheromones off as an only subconsciously perceptible advertisement for their charms. The males get to the arena as the sun sets, and the females keep them waiting until 11. Then the females get there and hover in front of each male in turn, checking out the epaulets and honking. After they make their choice and mate, the males “retire exhausted by 3 a.m.”

Tagged as: bat, mating

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Mating Week: Northern Elephant Seal (Mirounga angustirostris)

by JR Kinyak on March 2, 2011

in Carnivores,Theme Weeks

northern elephant seal

Northern elephant seal (click image to enlarge)


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There’s so much to say about elephant seals, and yet it’s so distasteful. These guys are rapists and baby-killers. Their necks are discolored by scars incurred during mating or fighting for mates, and one of my books, Wonders of Animal Life from 1928, lists “Sea elephants, frightfulness” in its index. In Living Mammals of the World, Ivan T. Sanderson says that they “present the most grotesque and revolting appearance, especially when they lounge around on shore in great misshapen, heaving masses under a hot sun, moaning, groaning, gurgling, and roaring.” A 1979 article in People about one of the top scientists studying elephant seals includes the sentence, “Says Le Boeuf bluntly, ‘It’s a rape society.’” (The title of the article is “Burney Le Boeuf Finds One Way to Pick Up a Seal of Approval.”)

I have a reprint of an 1874 book called The Marine Mammals of the Northwestern Coast of North America that includes a graphic account of the brutal way elephant seals were hunted for their blubber. Trust me, you probably don’t want to know, yet it’s not much worse than what the seals do to each other—except the blubber-hunters nearly drove the seals to extinction. Now they’re pretty healthily back in business in their habitat along the Pacific coast of North America.

And what is that business? Well, a dominant male controls a harem of females and can mate with them whenever he pleases. If a female objects, he holds her down with his massive body weight—up to three tons, and two or three times as much as the female weighs—and forces himself on her. Females have light-colored necks from all the scars they get when the males bite them during mating.

If a non-dominant male tries to mate with one of the females, the female starts screaming, which attracts the dominant male to defend his territory. At that point, he’ll get in a fight with the non-dominant male—a big, bloody fight, as any fight between two creatures that weight two tons would be. They beat each other with their noses and thrash around, sometimes suffocating other elephant seals in the process, especially babies. From Courtship in the Animal Kingdom by Mark Jerome Walters (1988):

Every spring along certain California beaches, bulls engage in bloody competition for female seals. The fight begins as a gruff shouting match with two males exchanging deep-throated roars. If one doesn’t retreat, then the shouting match escalates into combat…[T]hey slam their bludgeonlike noses into each other while trying to sink their large teeth into the neck of their opponent. Newborns are the most frequent victims as males throw their weight around, and the beaches resound with the shrill cries of crushed infants. Nearly half of the pups’ deaths in a single season are caused by battling males.

Walters goes on to say that sex is one of the major reasons for conflict among animals. “Spring is also the season when life’s astounding variety comes clearly into view—a richness that owes much of its existence to sex. And to which the world owes much of its woe.”

It certainly sounds like elephant seals lead woeful lives, and I’m glad that we humans have stopped contributing so murderously to their travails. But we are messing things up for them in another way, and that’s climate change. It seems that in warmer years, females give birth to more male babies. This is apparently because males and females have different feeding grounds. When it’s warmer, the food resources are more diffuse, and the females have to go further to find something to eat. If they have male babies, they won’t create competition for themselves the way they would if they had female young. So they’ve adapted to give birth to males when the weather is warm. Global warming could cause the proportion of male elephant seals to increase, which would mean more competition and more of the violence I discussed above. It could also mean that females have a harder time finding food, which would mean they’re undernourished and less likely to survive.

Tagged as: climate change, humans, ivan, mating, seal, threats

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