Musk Deer

Musk Deer

Continuing our series of posts about saber toothed mammals we come to a second family of living creatures.  Half way between the primitive chevrotains (mouse deer) and the familiar true deer (cervids) are the Moschidae, a family of small artiodactyls consisting of one genus with several similar species.  The musk deer are small delicate grazers which live in the forested mountains or alpine scrubland of Asia.  Musk deer weigh between 7 and 17 kilograms (15 and 37 lb) depending on gender, age, and species. Unlike true deer, the little creatures lack antlers, but male musk deer make up for this absence with a pair of elongated canine teeth which they use to fight for breeding rights.

Alpine Musk Deer (Moschus chrysogaster)

Like true deer, musk deer eat the tender shoots of trees and grasses, as well as berries, lichens, and mosses.  Females live in small territories of approximately 100 to 200 acres.  The territory of a dominant male will overlap several of the females’ territories.  Female musk deer give birth to a single fawn.  Musk deer are nocturnal or crepuscular.  They use their acute hearing and excellent sense of smell to flee from predators at the slightest hint of danger.

The skull of a male Siberian Musk Deer (Moschus moschiferus)

Male adult musk deer have a musk pouch located between their genitals and their umbilicus which they use to attract mates.  Unfortunately for the little saber toothed deer this pouch also attracts human hunters.  For centuries (or longer) musk has been a prized luxury good, so much so that, at times, prices have soared to $45,000/kg on the black market. The musk is said to have an incredibly complex aroma but the main notes are earthy, woody, and “animalic” (i.e. fecal).  Dried musk grain must be substantially tinctured with alcohol before it produces a perfume which is pleasant to humans.  The resultant substance however served as a mainstay of the perfume industry and as a cure-all nostrum in ayurvedic medicine until the creation of synthetic musk.  Poor musk deer from several species were nearly wiped out because of whatever mysterious power their sexual marking fluid has on humankind.

The Dwarf Musk Deer (Moschus berezovskii)

The Long Summer of the Eocene

The Eocene (Illustration by Bob Hynes for the Smithsonian Institution)

The Eocene epoch (which lasted from 56 million ago to 34 million years ago) was hot!  Temperate forests ran all the way to the poles.  Steamy tropical jungles grew in the latitude where Maine is now and the equatorial regions of earth were (probably) sweltering. Tropical reefs formed in the coastal waters around a heavily forested and ice-free Antarctica. Since there was not year-round ice at each pole, the sea levels were much higher.

A Global Map of the Early Eocene (map by Dr. Ron Blakey)

The Eocene was a time when most of the contemporary mammalian orders first appeared.  The earliest artiodactyls, perissodactyls, rodents, bats, probiscideans, sirenians, and primates all originated during this time.  Of course mammals were not the only story: the Eocene was also a time of great diversification for birds and many familiar orders of avians developed then.  Reptiles begin to put the setbacks which marked the end of the Cretaceous behind them and several giant new species emerged including an immense tropical ur-python and a host of crocodiles and turtles. It is harrowing to think that the first wee dawn horses and cute little early atiodactyls were forced to contend with a 13 meter long super snakes and giant crocodilians (which flourished in the great hot swamps of Alaska), but such is the case.

Titanboa with Ancient Crocodilian (painting by Jason Bourque)

The high temperatures of the Eocene are perplexing to scientists.  By contrast, the temperatures of the Paleocene (which was the first era of the Cenezoic and had directly preceded the Eocene) were much more temperate. In fact the temperature spike of 56 million years ago seems to have ended the Paleocene and brought about the diversification of Eocene life.  The rapid warming is known as the Palaeocene-Eocene thermal maximum and scientists have been vigorously debating what caused the climate change.  An immense amount of carbon seems to have entered the atmosphere at this time, which in turn led to greenhouse warming.  It remains controversial as to how such a large quantity of carbon got into the atmosphere.  Comet/meteorite impact, massive peat fires, and volcanic activity have been suggested as triggers, however supporting evidence is lacking.  The release of globally significant quantities of hydrocarbons–which had been trapped in undersea clathrates seems like a more feasible hypothesis, as does the idea that the earth’s orbit brought the planet closer to the sun for a time.

Phenacodus, a goat-sized grazer of the Eocene era (painting by Heinrich Harder)

The end of the Eocene was also linked to the carbon cycle.  Reduced carbon dioxide in the atmosphere seems to have led to global cooling and newly evolved varieties of grasses began to invade large swaths of the world.  Additionally two massive meteor strikes in Siberia and Maryland combined with substantial volcanic activity to finish off the long hot summer. But during the Oligocene, the era which followed the Eocene, the world was a much more familiar place inhabited by orders of animals which are still here with us today (or are us–since primates first evolved during the Eocene).