NATURE’S WEIRDEST CREATURES...
MUNTJAC DEER
Although common in the British countryside, a recent viral video has shed new light on the seemingly bizarre adaptations of the muntjac deer; facial glands that can open so wide, they can actually turn inside out. As the smallest species of deer in the UK, around the height of a small to medium-sized dog, muntjac have two sets of scent glands on their face that grow and swell, like balloons filling with air.
When relaxed, they look like nothing more than small bumps on the deer’s face, but to other muntjacs, they are a crucial tool for communication and bonding. As the scent glands expand, they secrete a personalised concoction of chemical compounds that convey information about a deer’s sex, age and reproductive status, as well as their overall health, wellbeing, and social hierarchy. A deer will rub their face against a tree (or other object), releasing their scent that acts like a calling card; a message to other creatures in the forest that the muntjac deer is present.
Muntjac also have a variety of vocalisations, ranging from soft grunting noises to something resembling a human scream. They’re also known as the ‘barking deer’ thanks to their loud, resonant (and repeating) bark, which sounds a bit like a loud cough.
This type of bark is unique to muntjacs, and they can be very vocal given their petite size. It’s often used as a territorial call, with males barking to attract a female, or to ward off predators. If you live near muntjacs, be warned, this barking can go on for many hours…
Nothing says ‘get out of the water quickly’ like the sight of a shark’s fin and the pulsing theme tune of the Jaws movie. Sharks are the ocean’s top predator. There are around 500 species, varying in size, diet and behaviour, lurking in waters all over the world. Their teeth come in all shapes and sizes, from the piercing, needle-like teeth of the goblin shark, to the crushing, flattened teeth of the angel shark, and the slashing razors of the great white. An extinct species of mackerel shark, known as the megalodon, had the biggest teeth of any known shark, with triangular gnashers measuring more than 17cm.
When an adult human loses a tooth, it’s game over and a trip to the dentist is needed to have an implant fitted. Sharks, however, can replace lost teeth throughout their life. They need to. Ground sharks, which are the largest order of sharks, including hammerheads and tiger sharks, lose around 35,000 teeth in a lifetime. They frequently fall out or become damaged when the fish are grappling with their prey, but the sharks are blessed with multiple rows of teeth, which are lined up, one behind the next. When a tooth falls out, the corresponding tooth in the row behind simply moves forward to take its place. And the one behind that one moves forward to take its place. And so on. It’s like a conveyor belt that’s made of teeth.
Working with catsharks, scientists have discovered pockets of stem cells inside the sharks’ mouths, which can divide to produce new, more specialised cells, which ultimately form the teeth that are needed to keep the conveyor belt stocked. The genes controlling this process have similar counterparts in humans, so now scientists are wondering if they could tweak the activity of these genes in people, to help us regrow lost teeth too.