Metazoa info

[Duke Guilmon]

Spotted Hyena



Crocuta Crocuta

Length: 44in to 73in

Weight: 110 to 190lbs

Life Expectancy: 25 years in the wild,41 in the zoo

First appeared: Late pliocene 3 to 2 million years ago.

Location: Hyenas are scattered across Africa mostly living in areas like Kenya and Somalia, and prefer to live on the Savannah



Taxonomy

Class:Mammal
Subclass:Theriiformes
Clade:Eutheria
Magnorder:Boreoeutheria
Superorder:Laurasiatheria
?: Zooamata or Euungulata
not yet ranked:Ferae
Order:Carnivora
Suborder:Feliormia
Family:Hyaenidae
Subfamily:Hyaeninae
Genus:Crocuta
Species:Crocuta Crocuta

Diet: Hyenas eat animals like zebras and wildebeest. Even dangerous animals like Rhinos and Cape Buffalo are hunted by spotted hyenas.

Anatomy

The skull of the spotted hyena is large and has a narrow sagittal crest,other hyenas don't have. The reason its skull has taken this path of evolution is due to the diet that it eats. The premolars and carnassials have evolved for bone crushing. The premolars have evolved so that they can crush bone while eating. The carnassials are located behind the premolars so that they don't take damage when they hyena is eating bones. The skull of the Spotted hyena gives the hyena a bite that is super dangerous. The muscle attachments of the hyena skull help the hyena have one of the strongest bite forces having a 800 kgf/cm2 bite force. This beats bears when it comes to biting through bone. Hyenas also have the strongest bones out of the entire kingdom of carnivora.

The strangest of all the Spotted hyena organs is the reproductive organs. Female hyenas have a reproductive organ the mimics that of the male hyena. This is another thing exclusive to spotted hyenas that other hyenas don't have. The reason for this is still being discovered, however some scientist say that the large amount of testosterone in the females might have something to do with it.

Another powerful organ of the hyena is the heart. The hyenas heart makes up 1% of its body weight. The large heart gives the spotted hyena more endurance meaning that even with its slow run,it can run long enough to catch up with its prey.

Spotted hyenas also have a special organ that they use to make a smell. This organ is a anal gland. Using this gland the hyenas can make a identifications of themselves. The smell can show age, strength, gender of the hyena and are used to mark territory. No two hyena smells are alike and this can help with identification.

The Spotted hyena also has a long digestive tract. This has evolved so that the hyena can absorb all the nutrients of its food and so that it can digest the bones that it eats.

Behavior:

Hyenas are social animals, that hang in large groups called clans. Unlike its social relatives, hyenas tend to have groups similar to that of baboon troops. Hyena clans can grow up to more then 40 individuals. Hyenas of a clan make loud calls so that when needed, the can call for reinforcements. Each hyena clan has a ranking system. No matter what male spotted hyenas always rank lower then the females. In fact the alpha male is as high in rank as the lowest female hyena, if not lower. The ranking system in hyenas clans are to make sure that there is not chaos. Feeding also depends on rank. The queen eats first and then it goes down the latter of rank. Hyenas of lower rank that have a successful hunt will try to eat as much as they can before their superiors arrive. Even the young inherit rank. The queens children will become the highest ranking out of all the cubs and will be the most aggressive, while lower ranking cubs will be less aggressive and may get picked on by their superiors. Each clan is also different and not just in size. Fur can be different, for example one clan may have very little spots and dark fur, while another will have a lot of spots and light fur. Behavior in each clan is also different. Some clans will play with each other, while other will have violence or even death between their own clan members. Parenting can differ as well. Females in one clan may only nurse their own offspring, while another females will nurse offspring that isn't theirs.


Despite the myth, hyenas aren't huge on scavenging. Most of the time hyenas hunt. However their strategy is different. They don't stalk their prey they walk right in the middle of the crowd. Hyenas tend to not scare big predators when their is only one. But hyena are searching for the weak,old,sick, and young. When they find what they're looking for they attack. Hyenas may not be fast but they run long so that they can tire out their prey. Hyenas however don't kill their prey when they catch it, they eat it alive.

Hyena clans will come into conflict with each other. Many times it is violent other times it's not. Most of the conflict between hyenas are for food. The most common stand off for food is the when hyenas try to take over the food by intimidating each other. However when hyenas do fight it gets violent. Hyenas will lose ears, limbs, and even faces during these fights.

Reproduction: Spotted Hyenas do not have a breeding season, though most births happen during the wet season. Hyena mating is difficult because of the females pseudo penis. The male must enter his penis very carefully into it so that he may be able to mate. All females in a clan are able to have young, but the dominant female gets a better area to give birth. Gestation takes about 3 months. Mothers are the only ones to really take care of their cubs, but depending other members may also help with raising them.

Interactions with other animals:

The two most dangerous animals to spotted hyenas are humans(homo sapiens) and lions(panthera leos). Humans do kill hyenas either on purpose or by accident. Human development may also infringe on the hyenas habitat. Lions are the hyenas nemesis. Lions will steal many hyena kills. The male lions will even kill the hyena queen for sport. However hyenas also kill female lions and may even steal some lion kills.

Another group of animals hyenas interact with are the cheetah(acinonyx jubatus) and the african leopard(panthera pardus pardus). Unlike the lion these two wild cats can't do much to the hyena. Cheetahs do have their kills stolen by hyenas and their is very little one can do. Even a single hyena can take on three cheetahs. The cheetah will slam its front paws on the ground repeatedly, but this does very little to hyenas. Leopards however fair better. They can't fight back against hyenas but they can drag their prey up into the trees with them, and this is good because hyenas can't climb. However if the spotted hyena catch up to them before they make the climb the leopard must then just climb with no food to eat.

Hyenas also have a thing with vultures. Vultures in Africa like the lappet-faced vulture(torgos tracheliotos) will fly over dinner. Hyenas look to the sky and head in the direction that the vultures are located. Hyenas must be careful though because they don't want to be attacked by them. However hyenas will get their way with vultures and get the free meal that the vultures found.


Are they playing or fighting?

Other sources:
http://www.arkive.org/spotted-hyaena/crocuta-crocuta/

http://www.youtube.com/user/ClanHyena

http://animaldiversity.ummz.umich.edu/ac...a_crocuta/

http://animals.nationalgeographic.com/an...als/hyena/