The Largest Land Mammal Ever

A human (black), an African Elephant (gray), a Mastodon (french blue) and a Paraceratherium (sky blue)

The largest land animal alive today is the mighty African elephant, however even the largest adult bull elephants were dwarfed by the largest land mammal ever to exist.  The giant herbivore Paraceratherium stood 5.5 metres (18 ft) tall at the shoulder.  When standing upright the creature’s head (which was approximately the same size as character actor Danny Devito) was about 8 metres (26 ft) above the ground.  Although debate continues about how much the beast weighed, reasonable estimates suggest it could have massed from 15 to 20 metric tons which means that the animals were as large as mid-sized sauropod dinosaurs from the previous era.  Partial skeletons of Paraceratherium were discovered by different scientists at different times–which has confusingly resulted in three different names for the genus: 1) Paraceratherium  which means”near horn animal” in Greek; 2) Indricotherium which was derived from a mythical Russian progenitor-monster called the Indrik-Beast; and 3) Baluchitherium which means “Baluchistan beast”, in honor of Baluchistan, an arid portion of the Iranian plateau, where a fossil specimen was unearthed.  Paleontologists prefer to call the genus “Paraceratherium,” however, thanks to TV specials and museum shows the name “Indricotherium” remains popular with the public.

Artist’s Conception of Paraceratheriums Migrating (from asecic.org)

Paraceratheriums were perissodactyls.  The giant creatures were most closely related to the living rhinoceroses (although they shared ancestors with tapirs and horses as well).  Paraceratherium’s immense size allowed it to eat the branches and leaves of large trees.  They ranged across what is now Central Asia across Iran, India, Pakistan, Mongolia, Kazakhstan, and China.  The various species of Paraceratherium had long graceful necks somewhat like that of Okapis.  Additionally they possessed nimble elongated upper lips with which to strip leaves off of branches.  These lips were no quite trunks but probably resembled the long grasping snout/lips of tapirs.  Although Paraceratherium was closely related to rhinoceroses, they lacked the rhino’s characteristic horns—their giant size meant they did not need them.  The genus originated in the Eocene and flourished during the Oligocene—a golden age of perissodatyls.  However as the global cooling became more pronounced in the late Oligocene, the great creatures gradually vanished.

Fossil Paraceratherium skeleton in a museum

Dugongs

A Dugong and Diver (photograph by Duane Yates)

There are about 120 living species of marine mammals (although that total may tragically become much smaller in the very near future).  Of this number, only one species is herbivorous.  The mighty dugong (Dugong dugon) is the last animal of its kind, a gentle lumbering remnant of the giant herds of sirenian grazers which once graced the world’s oceans. Dugongs are distinct from the three extant species of manatees (the world’s other remaining sirenians) in that they never require fresh water at any point of their lives.  Additionally dugongs possess fluked tails in the manner of dolphins and whales.

Dugong Range

Dugongs live in shallow tropical waters of the Indian Ocean and the Pacific Ocean.  They range from Madagascar to the Philippines, but are only common along the north coast of Australia (where conservation efforts and a limited human population have allowed them to live in peace).  Dugongs can swim in deep oceans for a limited time, but prefer to stay on continental shelves where they can feed on seagrass and marine algae.  Their all-salad diet does not prevent them from growing to substantial size: some individuals have been known to reach more than 3.5 meters in length (11 feet) and weigh over 950 kilograms (nearly a ton).  Although Dugongs can live more than seventy years, they reproduce extremely slowly.  Females gestate for over a year and then suckle their calf for around 18 months. Calves may stay with their mothers for many years after being weaned and need almost contact with their mothers for security and affection until they are almost grown. Young dugongs swim with their short paddle-like flippers, but adults use their tail for propulsion and only steer with their flippers.

Dugong and Calf

Dugongs have a variety of vocalizations with which they communicate.  Usually they live in small family units.  Great herds are not unknown but  seagrasses do not grow in sufficient quantity to support such numbers together for long.

Like the other sirenians, Dugongs have dense bones with almost no marrow (a feature known as pachyostosis).  It has been speculated that such heavy skeletons help them stay suspended just beneath the water in the manner of ballast.  The lungs of dugongs are extremely elongated, as are their large elaborate kidneys (which must cope with only saltwater).  Additionally, the blood of dugongs clots extremely rapidly.

Dugongs face a number of natural threats, particularly storms, parasites, and illnesses.  Because of their large size they are only preyed upon by alpha predators such as large sharks, killer whales, and salt-water crocodiles.  As with other marine animals, the greatest dangers facing dugongs come from humankind.  For millennia Dugongs have been hunted for meat, oil, and ivory. Traditional medicine from various portions of their range (wrongly) imputes magical properties to parts of their bodies. Worst of all, dugongs are frequent victims of boat collisions or are killed as by-catch by fishermen trying to catch something else.

Close-up of a Dugong (Julien Willem)

The Pika

A pika (from a breathtaking gallery of photos of Arunachal Pradesh and Assam by Yathin)

Hooray! This week Ferrebeekeeeper officially celebrates small herbivorous ground mammals! There are several reasons for this adorable theme, but chief among them are the week’s two prominent holidays:  1) Groundhog Day is on February 2^nd, 2011; and 2) the first day of the Chinese year of the rabbit takes place on February 3^rd, 2011.  Also I hope an endearing parade of little bewhiskered faces will help you forget your cabin fever and stay warm as this oppressive winter rages on.

Since humankind does not hibernate, I thought I would start the week with a non-hibernating lagomorph which, though not actually a farmer, is renowned for its haymaking abilities. This animal, the pika, is a close cousin to the rabbit (which will itself be amply celebrated on Thursday. Additionally, a world famous cartoon character, the Pikachu, may or may not be a pika.

A Pika Gathers Hay

Pikas are small densely furred animals of the family Ochotonidae which is part of the lagomorph order.  Lagomorphs most likely split from rodentlike forbears as far back as the Cretaceous–so the lepus and pikas both have an ancient heritage.  Pikas are generally diurnal or crepuscular and they eat grasses, sedges, moss, and lichen.  Most pikas are alpine animals, living on the mountain skree at or above the tree line (although a few burrowing species have moved down the mountains to the great central Asian steppes).  The 30 or so species of pikas are divided between Asia, North America, and Europe. Most Pikas live together in family groups (with the exception of North American Pikas which are maverick loners). Additionally, in Europe and Asia, pikas frequently share their burrows with nesting snowfinches.

Since pikas do not hibernate and they live on resource starved mountaintops, the animals harvest grasses in the summer and create little hay stacks so that their harvest will dry and be preserved.  Once these grasses dry out, Pikas store they hay in their burrows in order to provide both food and shelter during the brutal mountain winters. Unfortunately, the pikas are greedy.  They attempt to steal grass from their neighbor’s haystacks while simultaneously defending their own.  The ensuing fights are a major cause of pika mortality because the distracted combatants are easy prey for high altitude predators like hawks and ferrets.

Another pika (I'm sorry--online sources never tell me which species)

Even though Pikas have apparently been around for more than 65 million years, they get scant respect. Both Google auto-populate and my spell checker refuse to acknowledge the creatures and keep pushing me towards “pica”, an eating disease characterized by the consumption of non-food substances such as dirt or paper, or “Pikachu,” the mascot of the Pokemon children’s brand. This latter entity is a fictional yellow magical creature captured and made to fight as a gladiator by cruel Japanese anime children.  The Pikachu is capable of some sort of electrical attack. Pikachu may or may not have been based off of either the animal pika or a Japanese portmanteau combining the words for ‘spark’ and the noise a mouse makes.  The Pikachu’s cartoon features provide no help in assessing whether it is a pika or not, since the character looks eerily similar to a pika but doesn’t present any definitive trait (and possesses a most un pika-like tail to boot).  Although Pokemon’s star is mercifully beginning to set, the brand ruled childrens’ entertainment completely during the late 90’s.  Pikachu was ranked as the second best person of the year by Time magazine Asia edition in 1999 (finishing just below the not-quite out of the closet Ricky Martin, but ahead of Mini-me and J.K. Rowling).

Pikachu Float in the 2005 Macy's Thanksgiving Parade