The Gila Monster

Covered in pink and black bead-like scales, the Gila monster (Heloderma suspectum) is the largest lizard native to the United States. It is one of only two venomous lizards found in North America, along with Mexican beaded lizard. However, they are slow-moving and sluggish by nature so pose little threat to humans.

Gila Monster

These reptiles live in the deserts of southwestern North America, where they hunt insects and ground-dwelling vertebrates, including small mammals. Their name comes from Arizona’s Gila River basin – the area where they were first discovered. Gila monsters spend 90% of their time underground in burrows or rocky shelters, allowing them to stay cool in the desert heat.

Their oversized tails can be used to store large amounts of fat, letting Gilas to go for months without a meal. Unbelievably, these lizards may only consume as few as three big meals a year, and still maintain good health.

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You can clearly see the coloured beads that make up the Gila monster’s skin.

The Gila monster’s venom is a neurotoxin which would be extremely painful to humans, but there have been no reported deaths from being bitten by a Gila monster. Unusually for reptiles, the Gila monster does not inject its venom, instead it latches onto its victim and chews to allow neurotoxins to move through the grooves in their teeth and into the newly created wound. The most fascinating aspect of their venom is the proteins that it contains. A synthetic version of the protein exendin-4, derived from the Gila monster’s saliva, is used for the management of type 2 diabetes. Surprisingly, this protein has proved to be a highly effective treatment for diabetes, emphasising the ever-amazing wonders of wildlife.

The Gerenuk

Nicknamed the ‘giraffe gazelle’, the gerenuk (Litocranius walleri) is a long-necked antelope found in the woodland forests and open plains of the Horn of Africa (including Somalia, Ethiopia, Kenya, Djibouti and Tanzania). At first glance, this mammal may seem rather strange, but their unique appearance only highlights the gerenuk’s superb adaptability.

Gerenuk

Like many other species – past and present – that have evolved to have a long neck, the gerenuk uses this adaptation to browse leaves, twigs and branches growing out of the reach of other antelopes. Moreover, the gerenuk can stand straight using its slender, hindlegs. Overall, this allows the gerenuk to reach vegetation 2 metres above the ground – quite a stretch considering they are less than a metre tall when on all four legs. This adaptation has proved immensely useful for the gerenuk, especially when browsing opportunities are sparse.

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The gerenuk’s long neck and slender legs allow it to reach vegetation high off the ground.

Their magnificent horns, present only on males, are lyre-shaped, resembling an ‘S’, and can reach up to 40cm in length. Their brown coat is coffee-coloured on the top but a lighter tan colour on the sides. They also have a cream-coloured underbelly and a patch of white fur around each eye. Gerenuks have quite large eyes and ears so they can easily sense when a predator is nearby.

Gerenuks live in small social groups – each herd only contains around two to six individuals – and are usually comprised of a single sex. Due to their small herds, they can fall prey to a whole host of African predators. Major predators of the gerenuk include leopards, cheetahs, lions, spotted hyenas, painted wolves, jackals and caracals. Unlike most antelopes, the gerenuk does not have a specific breeding season, meaning they have offspring throughout the year. Therefore, they most constantly be alert for predators.

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A pair of females on the look-out for potential predators.

Although their population is estimated at around 95,000 individuals, the gerenuk is under threat. Their population has fallen by 25% in the last 14 years. As human populations grow, we build more settlements, more roads and more farms which are gradually consuming this species’ natural habitat. Their current conservation status is ‘near-threatened’, but if nothing is done, they could soon be uplisted to ‘vulnerable’.

 

Sources:

https://www.awf.org/wildlife-conservation/gerenuk

https://animalcorner.co.uk/animals/gerenuk/

https://en.wikipedia.org/wiki/Gerenuk

Hennessy, K., Wiggins, V. (2014) Animal Encyclopedia: The Definitive Visual Guide. 2nd edn. London. Dorling Kindersley.

The Mandrill

The largest of all monkeys, the mandrill (Mandrillus sphinx) is a vividly unique primate. The males have an unmistakable appearance – easily identifiable by the sky-blue and scarlet-red skin on their face, as well as an ombre of galaxy fading into crimson on their rump. This spectacular colouration makes the mandrill one of the most colourful of all mammals. Controlled by hormones, these colours grow brighter and starker when an individual gets excited. But these monkeys possess far more wonders than just their vivid skin.

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A dominant male mandrill foraging on the forest floor.

Found mainly in tropical rainforests across Cameroon, Gabon, Equatorial Guinea and Congo, the mandrill is an extremely social animal. They live in troops (occasionally called ‘hordes’) usually consisting of a dominant male, several females, a group of youngsters, and various non-breeding, lower-ranking males. These hordes can be colossal; sometimes several groups merge to form troops of 200 or more. However, mandrill society is not a tranquil utopia full of fun and games. It has a strict hierarchy. Mandrills have long canine teeth used principally for fighting and in display. Dominant males advertise their dominance with their intense colouration, and a temperament to match. Conflict can be deadly.

Generally, males weigh around 30kg whereas females usually weigh less than half of that, with an average weight of 12kg. Mandrills are one of the most sexually dimorphic animals, meaning the two sexes exhibit different characteristics. Whilst the males have this bulky and vivid image, the females have a far less obnoxious appearance. The female’s colouration is darker, but that does not mean they lack character; female mandrills have the vital role of raising the next generation.

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A female (left) grooming a male (right).

Primarily terrestrial primates, mandrills forage on the ground for fruits, roots, insects, reptiles and amphibians. Although, they have been known to consume the young of other species of monkey, and even small antelope when desperately hungry. Mandrills have short, but fully opposable thumbs – like those of the great apes – for grasping food and manipulating objects. They also have powerful jaw muscles, allowing them to crush tough plant foods.

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Sadly, the mandrill is considered vulnerable by the ICUN. They are often hunted for bushmeat, and many African cultures consider them a delicacy. In some areas, they are considered a pest because they will destroy crops of local villages, and are subsequently killed. Deforestation, urbanisation and the growth of agriculture are also rapidly constricting their natural habitat. Thankfully, conservation and re-introduction schemes are helping to conserve the mandrill population. Charles Darwin once said “no other member in the whole class of mammals is coloured in so extraordinary a manner as the adult male mandrill’s”. Such an impressive mammal deserves protection.

 

Sources:

https://www.nationalgeographic.com/animals/mammals/m/mandrill/

https://en.wikipedia.org/wiki/Mandrill

https://www.monkeyworlds.com/mandrill/

Hennessy, K., Wiggins, V. (2014) Animal Encyclopedia: The Definitive Visual Guide. 2nd edn. London. Dorling Kindersley.

The Common Octopus

With their extraordinary camouflage techniques and ingenious defences, the common octopus (Octopus vulgaris) is one of the most intelligent of all the invertebrates. This species is a mollusc belonging to the class Cephalopoda, and is widespread in tropical and warm temperate oceanic waters. Their vast distribution is a testament to the octopus’ ability to continuously adapt.

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The common octopus has a unique and unmistakable appearance. They have eight grasping arms, or tentacles, which are also used for crawling along the sea floor. Each tentacle can be up to 1 metre in length and is lined with two series of cup-like ‘suckers’. These give the octopus a superb grip, acting like studs on the bottom of football boots. The suckers also have receptors that enable the octopus to taste what is touching (as I said, this animal is incredibly unique). Their huge, bulbous head is actually a fleshy mantle enclosing a cavity that contains vital organs, including gills for breathing. Another magnificent feature of the common octopus is their eyesight. This mollusc has two prominent eyes with a horizontal, slit-shaped pupil which give them surprisingly excellent vision.

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Their ‘suckers’ make them excellent climbers.

This octopus is a predator of crustaceans, among other prey, and has a secret weapon hiding in its underside – a beak. Its jaws are a parrot-like peak, which is strong enough to penetrate the carapace (shell) of a crab or lobster. This beak can deliver a nasty bite and hides a venomous saliva used for subduing prey. They may also release a cloud of black ink to disorientate their meal before attacking. This ink is released from a funnel just behind its head and is mainly used as a defence mechanism. When faced with an enemy, they will release this ink (which contains chemicals that dull their attacker’s sense of smell) and swiftly flee from the scene. This funnel has two other main uses: to expel water after gills have extracted oxygen and to rapidly discharge water as jet propulsion for a quick getaway. There is no denying that this animal is exceptionally creative in its methods of predation and defence.

But their brilliance does not end there. For one, they can squeeze through minuscule cracks and crevices – any hole that’s not smaller than their beak. Furthermore, the common octopus can change colour in an instant. Their skin contains special cells called chromatophores. These contain pigment which can change the octopus’ colour and even texture, allowing them to blend in with their surroundings or to signal its mood if angry or afraid. Their camouflage is one of the best in the animal kingdom; predators such as sharks, eels, and dolphins swim by without even noticing them. I’m starting to question if there’s anything this animal can’t do.

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The common octopus can blend into almost any environment.

In spite of its remarkable adaptations, the common octopus is short-lived, with a lifespan of 1 to 2 years in the wild. It takes little more than a year to mature and spawn their own offspring, Both mother and father die soon after mating as their time is completely focused on caring for and brooding their eggs. Upon hatching, an infant octopus enters the big, blue world with half a million of its siblings – ready to repeat this cycle all over again. The common octopus is the first invertebrate of my blog, and deservedly so. Their exceptional array of unbelievable characteristics and adaptations make them a true wonder of wildlife.

 

Sources:

https://www.nationalgeographic.com/animals/invertebrates/c/common-octopus/

http://www.thecephalopodpage.org/MarineInvertebrateZoology/Octopusvulgaris.html

https://en.wikipedia.org/wiki/Common_octopus

Hennessy, K., Wiggins, V. (2014) Animal Encyclopedia: The Definitive Visual Guide. 2nd edn. London. Dorling Kindersley.

The Nile Crocodile

The largest freshwater predator in Africa, the Nile crocodile (Crocodylus niloticus) is a formidable hunter with a great historical significance. They are widespread throughout sub-Saharan Africa, where they feed mainly on fish – like their Indian relative, the Gharial. However, these reptiles are opportunists so will attack almost anything unfortunate enough to cross its path, including zebras, wildebeest, small hippos, warthogs, bushpigs, porcupines, birds, and even other crocodiles. Once they have made a kill, they will rip off and swallow chunks of flesh, using the classic “death roll” to tear off particularly stubborn bits of meat.

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The Nile crocodile is possibly the second largest extant reptile in the world, after the huge saltwater crocodile. They can reach up to 6 metres in length, and weigh over 1000 kilograms in extremely rare cases. Though normally, adults don’t exceed 5 metres, and weigh around 500 kilograms. These crocs are quite sociable animals; sharing their basking spots and food with others. Their hierarchy is strict and determined solely by size and strength.

In the Maasai Mara National Reserve in Kenya, Nile crocodiles enjoy an annual feast. This reserve is famous for the annual migration of zebra, Thomson’s gazelle, and wildebeest to and from the Serengeti every year, known as the Great Migration. During this migration, these mammals must cross the Mara river – a river that is home to hundreds of hungry crocodiles. As huge herds of desperate wildebeest and zebra charge through the river, the crocodiles relish in the free buffet. These crocodiles have adapted, ingeniously, to exploit the delicious meals on offer.

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A Nile crocodile hunting a wildebeest in the Mara river.

Not only are Nile crocodiles superb predators, they also have an incredible past. Modern crocodiles have been around for about 80 million years, and the fact that they are still here today is a testament to their wonderful ability to adapt. In Ancient Egypt, the Nile crocodile was seen as the biggest and most dangerous predator; feared by many. However, the Egyptian people also had some admiration for these creatures – the Egyptian deity Sobek was based upon the crocodile. Mummified crocodiles and crocodile eggs have even been found in Egyptian tombs!

These reptiles were hunted close to extinction in the mid-1900s, but local and international conservation measures have helped populations to recover in most areas. Thankfully, their status is looking secure. The Nile crocodile has an undeserved reputation of being a vicious and ruthless man-eater, however incidents between people and crocodiles are rare. It is estimated that 200 people are killed each year by the Nile crocodile, a minuscule number when compared to the 1.25 million people who die in road crashes every year.

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Nile crocodiles are opportunists – they don’t actively hunt humans but will take an easy meal if presented with one. Crocodiles have been around far longer than we have. We should show them the respect they deserve.

 

Sources:

https://www.nationalgeographic.com/animals/reptiles/n/nile-crocodile/

http://www.krugerpark.co.za/africa_crocodiles.html

https://en.wikipedia.org/wiki/Nile_crocodile#Hunting_and_diet

https://en.wikipedia.org/wiki/Sobek

The Red Panda

The red panda (Ailurus fulgens) is an arboreal, solitary mammal native to the high-altitude, temperate forests of the eastern Himalayas and southwestern China. The red panda’s unique appearance has caused some confusion among zoologists. Up until recently, some zoologists classified the red panda with the raccoons (Procyonidae), whilst others placed it in the bear family (Ursidae, a group which includes the giant panda). However, analysis of their evolutionary relationships showed that they differ so greatly from both the giant panda and raccoon that they warrant their own family, Ailuridae.

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These climbers have superb balance up in the trees.

The red panda is roughly the size of a domestic cat, but unlike carnivorous cats, these climbers feed mainly on bamboo. They are not fussy creatures though, as they may also feed on birds, eggs, insects, flowers, berries and small mammals when the opportunity presents itself. Red pandas are usually crepuscular, meaning they are most active at dawn and dusk, and live solitary lives, only coming together to mate. Common predators of the red panda include the snow leopard and martens, but if they feel threatened they will rapidly flee by climbing up the nearest tree. If they have no other option, they may even stand on their hind legs to make themselves appear larger and use their claws to desperately slash at their enemy.

Their striped, bushy tails have three main purposes: for balance up in the trees; for camouflage in their habitat of moss and lichen-covered vegetation; and for warmth, especially during the harsh Himalayan winters. Another fascinating adaptation of the red panda is their claws. They have strong, curved, semi-retractable claws which are designed to grasp and tear their main food source – bamboo.

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Red pandas will use their bushy tails for warmth.

With their adorable, patchy face and their fluffy, reddish-brown coat it is hard not to adore these little guys. But sadly, many do not show the worthy respect to the red panda. The red panda is endangered and the wild population is estimated at fewer than 10,000 individuals. Their main threat is habitat loss and fragmentation caused by widespread deforestation as agriculture and human population pressure constrict their native range. Another major threat for the red panda is poaching, especially in China where the population of red pandas has fallen by 40% in the past 50 years.

The Grévy’s Zebra

The largest wild species in the horse family (Equidae), the Grévy’s zebra (Equus grevyi) is a perissodactyl (odd-toed ungulate) found only in certain regions of Ethiopia and Kenya. They are one of three species of zebra, the other two being the Plain’s zebra (Equus quagga) and the Mountain zebra (Equus zebra). This herbivore lives in semi-arid grasslands where it grazes on many different types of grass which other species may not be able to.

Aside from their unique pattern of stripes, one of the most distinctive features of the Grévy’s zebra is their large, mickey-mouse-esque ears – much larger than the ears of their cousins. They also have long legs which allow them to reach 40mph when sprinting.

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A herd of zebras, also known as a zeal or dazzle.

Unlike the plains zebra, Grévy’s do not live in harems – a group of females controlled by a dominant male (called a stallion). Instead, they live in herds with loose social structures and lack a particular dominant male. These social groups may contain foals who, unlike their parents, have a brown and white striping which gradually darkens into a black and white coat as they grow. Grévy’s zebras have a relatively long gestation period of 13 months resulting in the birth of a single foal. Amazingly, newborn foals can stand after six minutes, walk after 20 minutes, and they can run after an hour. This adaptation means foals can join the herd and evade predators just after they have been born.

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Foals have a brown and white striping.

Grévy’s zebra once roamed a vast area of East Africa but have since become restricted to the horn of Africa. They are now considered endangered, with their wild population totalling no more than 2,500 individuals. In the past, their main threat was poaching for their striped skin but now their main threats seems to be habitat loss and competition with livestock, cattle in particular. Moreover, with their current population being so small and fragmented, this species may soon find it difficult to reproduce and expand the gene pool.

The Grévy’s zebra got its name in 1882 when the government in Abyssinia (the Ethiopian empire) sent one of these zebras to France. The president at the time was Jules Grévy and subsequently this new species was named in his honour. Although I would have personally preferred Mickey’s zebra.