Showing posts tagged amphicyon

Killer Cave Lured Ancient Carnivores to Their Death

by Tia Ghose

A cavern in Spain may have lured ancient carnivores to their deaths by offering the promise of food and water, new research suggests.

The new study, published today (May 1) in the journal PLOS ONE, may explain how the carcasses of several carnivore species, including saber-toothed cats and “bear dogs,” wound up in an underground cavern millions of years ago.

“Only the carnivores were daring enough to enter,” said study co-author M. Soledad Domingo, a paleontologist at the University of Michigan. “But they were unable to make their way out.”…

(read more: Live Science)

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(images: 1 - illustration of sabertooths with rhino in ancient cave by Mauricio Anton; 2 - photo of Sabertooth skull by Soledad Domingo; 3 - illustration of cave history by Anton, Domingo, Sanchez; 4 - fossil skeleton of ancient “Bear-Dog” by ghedoghedo | Wikimedia)

lostbeasts:  Bear Dog

Amphicyonidae was a family of large carnivores, possibly early ursids, that lived during most of the Tertiary period. They grew from about 5kg up to 100-600kg. Earlier amphicyonids were far more wolf-like than those later, which were more bear-like.

(Reblogged from lostbeasts)
The Bear Dog (Amphicyon major) * click image to read text/see larger image (source unknown) View high resolution

The Bear Dog (Amphicyon major)

* click image to read text/see larger image

(source unknown)

Giant bear-dogs of the genera Amphicyon and Ischyrocyon (Carnivora, Amphicyonidae, Amphicyoninae) were the largest carnivorans in North America during middle and late Miocene (17.5-8.8 Mya) with a dental and skeletal morphology that combined features found in living Ursidae, Canidae, and Felidae. Bear-dogs probably pursued their prey (mediportal ungulates) for a longer distance but at a slower speed than do living ambush predators. Upon catching up to its prey a bear-dog probably seized it with powerfully muscled forelimbs and killed it by tearing into its ribcage or neck with canines set in a narrow rostrum… From: Ecomorphology of the giant bear-dogs Amphicyon and Ischyrocyon (http://www.informaworld.com/smpp/content~content=a769171329&db=all) View high resolution

Giant bear-dogs of the genera Amphicyon and Ischyrocyon (Carnivora, Amphicyonidae, Amphicyoninae) were the largest carnivorans in North America during middle and late Miocene (17.5-8.8 Mya) with a dental and skeletal morphology that combined features found in living Ursidae, Canidae, and Felidae. Bear-dogs probably pursued their prey (mediportal ungulates) for a longer distance but at a slower speed than do living ambush predators. Upon catching up to its prey a bear-dog probably seized it with powerfully muscled forelimbs and killed it by tearing into its ribcage or neck with canines set in a narrow rostrum… 

From: Ecomorphology of the giant bear-dogs Amphicyon and Ischyrocyon 

(http://www.informaworld.com/smpp/content~content=a769171329&db=all)

The Bear Dog (Amphicyon ingens) by Retrieverman With an estimated weight in excess of 1300 pounds, Amphicyon ingens was the largest of bear dog family. They evolved from wolf-like ancestors into bear-like creatures. The wolf body-type is actually a primitive carnivore body-type. Even the early hyenas, which are feliform Carnivores, looked more like wolves than hyenas. It has traditionally been suggested that bear dogs were close relatives of bears, but because the early ones looked so much like wolves, it has been suggested that they are actually derived from early caniforms,  the suborder that includes both modern dogs and bears. These animals had to have been ambush hunters, much like the big cats.  The prey in those days was big and slow. When pack-hunting Borophaginae came into North America (such as Epicyon), it is thought that they outcompeted Amphicyon. It is an interesting theory. We do know that modern wolves tend to dominate cougars. A cougar can kill a wolf on its own, but it cannot withstand competition from a pack of wolves. Wolves are better able to use a wider array of prey sources and take up all the best hunting grounds, leaving the cougar, a deer and elk hunting specialist, to eke out an existence on the margins… (read more: Retrieverman) View high resolution

The Bear Dog (Amphicyon ingens)

by Retrieverman

With an estimated weight in excess of 1300 pounds, Amphicyon ingens was the largest of bear dog family. They evolved from wolf-like ancestors into bear-like creatures. The wolf body-type is actually a primitive carnivore body-type. Even the early hyenas, which are feliform Carnivores, looked more like wolves than hyenas. It has traditionally been suggested that bear dogs were close relatives of bears, but because the early ones looked so much like wolves, it has been suggested that they are actually derived from early caniforms,  the suborder that includes both modern dogs and bears.

These animals had to have been ambush hunters, much like the big cats.  The prey in those days was big and slow. When pack-hunting Borophaginae came into North America (such as Epicyon), it is thought that they outcompeted Amphicyon.

It is an interesting theory. We do know that modern wolves tend to dominate cougars. A cougar can kill a wolf on its own, but it cannot withstand competition from a pack of wolves. Wolves are better able to use a wider array of prey sources and take up all the best hunting grounds, leaving the cougar, a deer and elk hunting specialist, to eke out an existence on the margins…

(read more: Retrieverman)

Bite of the Bear Dog by Brian Switek Between 23 and 16 million years ago, just outside of where the city of Lisbon, Portugal sits today, there lived a unique mix of mammals which would have seemed both strange and familiar. From bones and footprints left in fossilized feces, paleontologists have found that rhinoceros, deer, horses, antelope, and elephants browsed and grazed in the ancient ecosystem, and many were preyed upon by archaic carnivores such as the fearsome amphicyonids (popularly known as “bear-dogs“). That such confrontations occurred can readily be inferred by the presence of large predators and prey in the same place, but direct evidence of interaction is rare. It does not require a stretch of the imagination to envision a large bear-dog grappling a fleeing antelope or rhinoceros to the ground, but how do we really know that such events took place? Without a time machine, it can be extremely difficult to tease out the relationships between extinct organisms, but every now and then paleontologists find a rare specimen which records the interaction of two species. One such specimen, a bit of the left lower jaw from the rhinoceros Iberotherium rexmanueli, was described by scientists Miguel Antunes, Ausenda Balbino, and Léonard Ginsburg in 2006. Although rather plain-looking at first sight, the specimen is remarkable for exhibiting a series of pits and scratches that were most probably made by the bear-dog Amphicyon giganteus… (read more: Wired Science)     (image: Charlene Letenneur) View high resolution

Bite of the Bear Dog

by Brian Switek

Between 23 and 16 million years ago, just outside of where the city of Lisbon, Portugal sits today, there lived a unique mix of mammals which would have seemed both strange and familiar. From bones and footprints left in fossilized feces, paleontologists have found that rhinoceros, deer, horses, antelope, and elephants browsed and grazed in the ancient ecosystem, and many were preyed upon by archaic carnivores such as the fearsome amphicyonids (popularly known as “bear-dogs“). That such confrontations occurred can readily be inferred by the presence of large predators and prey in the same place, but direct evidence of interaction is rare. It does not require a stretch of the imagination to envision a large bear-dog grappling a fleeing antelope or rhinoceros to the ground, but how do we really know that such events took place?

Without a time machine, it can be extremely difficult to tease out the relationships between extinct organisms, but every now and then paleontologists find a rare specimen which records the interaction of two species. One such specimen, a bit of the left lower jaw from the rhinoceros Iberotherium rexmanueli, was described by scientists Miguel Antunes, Ausenda Balbino, and Léonard Ginsburg in 2006. Although rather plain-looking at first sight, the specimen is remarkable for exhibiting a series of pits and scratches that were most probably made by the bear-dog Amphicyon giganteus…

(read more: Wired Science)     (image: Charlene Letenneur)

“Bear Dogs” (family Amphicyonidae)  … an extinct family of large terrestrial carnivores belonging to the suborder Caniformia (meaning “dog-like”) and which inhabited North America, Europe, Asia, and Africa from the Middle Eocene subepoch to the Pleistocene epoch 46.2—1.8 Mya, existing for approximately 44.4 million years. Amphicyonids, often referred to as “bear dogs”, crossed from Europe to North America during the Miocene epoch and are considered an Old World taxon. (skeleton of Amphicyon ingens, by Ghedoghedo) Amphicyonids were as small as 5 kg (11 lb) and as large as 100 to 600 kg (220 to 1,300 lb) and evolved from wolf-like to bear-like. The diet of the amphicyonids was fully carnivorous as opposed to hypercarnivorous to mesocarnivorous in Canidae. While amphicyonids have traditionally been viewed as closely related to ursids (bears), some evidence suggests that they may instead be basal caniforms. (Hunt, 2004b). They were about as tall as the American black bear and were most likely ambushers because their legs were made for short, sudden bursts of speed. Bear-dog also nested their young in underground burrows… (read more: Wikipedia)      View high resolution

“Bear Dogs” (family Amphicyonidae) 

… an extinct family of large terrestrial carnivores belonging to the suborder Caniformia (meaning “dog-like”) and which inhabited North America, Europe, Asia, and Africa from the Middle Eocene subepoch to the Pleistocene epoch 46.2—1.8 Mya, existing for approximately 44.4 million years. Amphicyonids, often referred to as “bear dogs”, crossed from Europe to North America during the Miocene epoch and are considered an Old World taxon.

(skeleton of Amphicyon ingens, by Ghedoghedo)

Amphicyonids were as small as 5 kg (11 lb) and as large as 100 to 600 kg (220 to 1,300 lb) and evolved from wolf-like to bear-like. The diet of the amphicyonids was fully carnivorous as opposed to hypercarnivorous to mesocarnivorous in Canidae. While amphicyonids have traditionally been viewed as closely related to ursids (bears), some evidence suggests that they may instead be basal caniforms. (Hunt, 2004b). They were about as tall as the American black bear and were most likely ambushers because their legs were made for short, sudden bursts of speed. Bear-dog also nested their young in underground burrows…

(read more: Wikipedia)