Post by rock on Apr 25, 2019 22:24:53 GMT 5
thylacoleo
Thylacoleo ("pouch lion") is an extinct genus of carnivorous marsupials that lived in Australia from the late Pliocene to the late Pleistocene (2 million to 46 thousand years ago). Some of these "marsupial lions" were the largest mammalian predators in Australia of that time, with Thylacoleo carnifex approaching the weight of a small lion. The estimated average weight for the species ranges from 101 to 130 kg. Pound for pound, Thylacoleo carnifex had the strongest bite of any mammal species living or extinct; a T. carnifex weighing 101 kg (223 lb) had a bite comparable to that of a 250 kg African lion, and research suggests that Thylacoleo could hunt and take prey much larger than itself.[2] Larger animals that were likely prey include Diprotodon spp. and giant kangaroos. It seems improbable that Thylacoleo could achieve as high a bite force as a modern-day lion; however, this might have been possible when taking into consideration the size of its brain and skull. Carnivores usually have rather large brains when compared to herbivorous marsupials, which lessens the amount of bone that can be devoted to enhancing bite force. Thylacoleo however, is thought to have had substantially stronger muscle attachments and therefore a smaller brain. Canids possessed elongated skulls, while cats tend to possess foreshortened ones. The similarities between cat morphology and that of Thylacoleo indicates that although it was a marsupial, biologically it possessed greater similarities to cats, and as a result had a higher capacity for bite strength than other animals within its own infraclass.[3]
It also had extremely strong fore limbs, with retractable, cat-like claws, a trait previously unseen in marsupials. Thylacoleo also possessed enormous hooded claws set on large semiopposable thumbs, which were used to capture and disembowel prey. The long muscular tail was similar to that of a kangaroo. Specialised tail bones called chevrons allowed the animal to balance on its back legs, and freed the front legs for slashing and grasping.[4]
Its strong forelimbs, retracting claws, and incredibly powerful jaws mean that Thylacoleo possibly climbed trees and perhaps carried carcasses to keep the kill for itself (similar to the leopard today).[5] The climbing ability would have also helped them climb out of caves, which could therefore have been used as dens to rear their young.[6]
Due to its unique predatory morphology, scientists repeatedly claim Thylacoleo to be the most specialised mammalian carnivore of all time.[7] Thylacoleo had vertical shearing 'carnassial' cheek teeth that are relatively larger than in any other mammalian carnivore.[2] Thylacoleo was clearly derived from the diprotodontian ancestry due to its incisor morphology and is distinguished by the pronounced development of upper and lower third premolars which functioned as extreme carnassials with complementary reduction in the molar teeth row.[8] They also had canines but they served little purpose as they were stubby and not very sharp.[9]
Thylacoleo was 71 cm (28 in) at the shoulder and about 114 cm (45 in) long from head to tail. The species T. carnifex is the largest, and skulls indicate they averaged 101 to 130 kg (223 to 287 lb), and individuals reaching 124 to 160 kg (273 to 353 lb) were common, and the largest weight was of 128–164 kg (282–362 lb).[10] Fully grown, Thylacoleo carnifex would have been close to the same size as a jaguar.While considered a powerful hunter, and a fierce predator, many today would assert that due to its physiology Thylacoleo was, in fact, a slow runner, limiting its ability to chase prey. Analysis of its scapula suggests "walking and trotting, rather than climbing ... the pelvis similarly agrees with that of ambulators and cursors [walkers and runners]". "These bones indicate that Thylacoleo was a slow to medium-paced runner, which is likely to mean it was an ambush predator. That fits with the stripes: camouflage of the kind one would need for stalking and hiding in a largely forested habitat (like tigers) rather than chasing across open spaces (like lions).”[12] It may have functioned generally much like a larger analog of the Tasmanian devil.[6] New evidence also suggests that it may have been arboreal, and was at the very least capable of climbing trees.
At the site at Lancefield, many bones have been excavated and have been discovered to be a part of an estimated several hundred thousand diverse individuals. Some of those bones had strange cuts on their surfaces. Two likely explanations follow from this: marks were produced by prehistoric humans during butchering or by the teeth of Thylacoleo carnifex. Through archaeological and paleoecological findings, researchers concluded that the T. carnifex had caused all the cut marks. Because of their large size, the population had to feed on other species just as large as their own just to avoid an imbalance in their diets. They may have killed by using their front claws as either stabbing weapons or as a way to grab their prey with strangulation or suffocation.
spotted hyena [pack of 6]
The Spotted Hyena is the largest of the hyena family which also includes the brown hyena, the striped hyena, and the aardwolf. They have an unusual appearance due to their long powerful neck, uneven leg length (front legs are longer), and short thick yellow-grey fur which is covered in a spot pattern. A short mane of hair stands upright on the Spotted Hyenas back, creating a “Mohican” hairstyle for the hunter!
No! Every Spotted Hyena has a different set of spots, and this variety of patterns allows individuals to be recognised easily.
Spotted Hyenas can be found in a range of habitats within Sub-Saharan Africa. From semi-desert and savannah to woodlands and mountains, these strong mammals can survive as high up as 4100m! Currently, the largest populations lie within the Serengeti (Tanzania and Kenya) and the Kruger National Park (South Africa).
Unlike other mammals, the Spotted Hyena does not use a den for resting. Instead, they make use of shaded holes and pools during the day, and splash around in water holes to cool down!
As a predator, the Spotted Hyena eats the most meat out of all the hyena species. An average meal for these patterned creatures can include up to 14.5kg of meat! Typical prey consists of wildebeest, zebra and various antelope species, although if living near livestock they are known to steal a sheep or two! When scavenging, Spotted Hyenas can eat larger animals such as giraffes and elephants, and can even fully digest their bones.
Spotted Hyenas have been found to hunt and catch fish, tortoises and pythons in order to survive! It seems this intelligent species can escape hunger in many ways. Evolution has also allowed the Spotted Hyena to be very efficient in its water use, which is perfect for desert-living individuals!
The main rival for the Spotted Hyena is the lion as they live in similar habitats with similar prey choice. Often the Spotted Hyena can do all the hard work that leads up to a kill, only to be approached by a hungry group of lions who steal it away! Fights can break out in this situation, so Spotted Hyenas need to be always alert. If working in a group, they are capable of scaring the lions away.
Spotted Hyenas can also compete with one another during a feed, speeding up to see who can finish first!
Are Spotted Hyenas sociable?
Yes! Groups of hyenas are known as clans. Clans can include up to 100 members. Unlike many other species, females are larger than males and take charge of the clan!
Communication is through fascinating vocalisations, including their signature giggle. Spotted Hyenas tend to laugh when they are feeling excited or nervous, and make a whooping noise to call for their young or warn off predators. Within the clan, Spotted Hyenas say hello by squealing and groaning.
Spotted Hyenas usually give birth to young within den areas and upgrade them to a “kindergarten” area shortly after. This allows them to meet other cubs and compete for dominance, without the helping hand of their mother. One their status has been proven, Spotted Hyenas teach their cubs how to hunt and protect themselves!
The population of Spotted Hyenas is estimated to be between 27-47,000, and they are known to be of Least Concern status on the IUCN Red List. However, this number is decreasing as a result of poor public perception that is leading to persecution.
When living in an unprotected area, the Spotted Hyena is targeted by hunting, trapping, and poisoning. This is because of concern that they can kill livestock, although the actual level of predation is thought to be low. Drought and deforestation may also be affecting the Spotted Hyena by reducing available habitat and altering the food chain.
Increasing the extent of protected areas within the hyena range and improving the level of protection and enforcement will be key to sustaining a healthy population of hyenas in the long-term. Equally important, however, is working with local people within to address their negative perceptions and to resolve any conflicts that may arise. The IUCN published a “Hyena Status Survey and Conservation Action Plan” back in 1998 that sought to address persecution and to promote livestock protection plans for worried farmers. Various anti-predation farming methods have been trialled since its launch, and visiting tourists are also now engaged with Spotted Hyena conservation.
The Spotted Hyena can chase its prey reaching speeds of 37mph
The Spotted Hyenas laugh resembles that of a human, and became popular during their appearance in Disney’s ‘The Lion King’
Although they have a close resemblance to a dog, Spotted Hyenas are actually closer in relation to cats!
Special acids within the Spotted Hyenas stomach allow them to digest materials that other mammals cannot, including bones
The Spotted Hyena has a different ear shape than the brown hyena, with a smaller and more rounded appearance!
