Remembering 5 Amazing Animals That Went Extinct Due To Human Activity

Yesterday, May 15th 2020, was World Endangered Species Day.

Researchers, conservationists, wildlife enthusiasts and photographers took to social media to spread the message about animals that were on the IUCN Red List. They spoke about animals that are classified as Vulnerable & Endangered and spoke of how humans have the power to safeguard their uncertain future.

But at this point, I realized that talking about the uncertain futures of currently-alive animals just wasn’t enough. If we don’t show people what the impact of human activity and the resultant climate change looks like, we won’t be able to garner enough compassion and love towards conservation.

So, I’ve decided to take a new route. To show the world the magnificent creatures who were once with us, but who are now lost to us forever, thanks to deforestation, pollution, rising temperatures – and every other human-made menace.

Here’s a list of 5 brilliant, beautiful and extinct animals whose deaths we’re responsible for: 

Steller’s Sea Cow

This gentle aquatic giant became extinct a mere 30 years after it was discovered in 1741! They were hunted to death by sailors on the sea, for their meat and fur. The hunting was so fast and relentless, the poor animals didn’t have enough time to reproduce and replenish their lineage.

Steller’s Sea Cow belonged to the same class to which today’s manatees and dugongs belong. They were a whopping 30 feet long and at one point you could see them languidly grazing on the sea bed with their calves.

The sad thing is, the Steller’s Sea Cow was driven to extinction before it could even be properly studied. As a result, we know so little about it. Such a huge loss to the world!

Steller’s Sea Cow (Source)

 

Atlas Bear 

The one and only bear species to originate from Africa, Atlas bears were found across the African continent from Libya to Morroco. Resembling smaller versions of North American bears in appearance, Atlas bears were driven to extinction in the mid-1800s.

The rise of the Roman Empire brought about the fall of the Atlas bear population. Once Roman emperors started conquering parts of Africa, troops would capture Atlas bears and take them captive to Rome. There, these creatures would be forced to fight in public games (called Ludi), against deadly opponents like armed gladiators and other animals like tigers and lions. To break the bears’ spirits, trainers would starve and whip them into submission.

Atlas bear (Source) 

 

Laughing Owl 

Also known as the whēkau, this avian species was once the glory of New Zealand. Nesting on the ground and feeding on everything from insects to bats to ducks to kiwis, they were one of the most fearsome predators on the island. It was named the “laughing owl” because of its unique cry, which sounded like a shrieking laugh.

But the arrival of settlers to New Zealand and the deforestation and construction of cities that followed, pushed these birds closer to humans, where they lost access to their normal food, which was deeper in the jungles.

Additionally, the introduction of non-local animals like cats, rats, ferrets and weasels into New Zealand hastened the Laughing Owl’s journey to extinction. Not having evolved the skills needed to fend-off these new predators, Laughing Owls died a slow and painful death.

Laughing Owl (Source)

 

Caspian tiger

It’s a known fact that the tiger is one of the most endangered species on the planet. While some headway is being made in tiger conservation today, this wasn’t the case during early-to-mid 19th Century.

Once found all over Central Asia, the Caspian tiger species met a tragic end sometime in 1970 as a result of an illegal hunting expedition in Turkey’s Hakkari province. This type of indiscriminate hunting of the tiger for its fur, claws and teeth; plus the illegal trade of Caspian tiger cubs, forced the magnificent species to extinction.

Today, you can see similar human activities driving other tiger species towards extinction. If you’ve watched the show Tiger King, you’ll know that keeping tigers in zoos and so-called “rescue centers” (yes, I’m talking to you Carole – and others like her), will not save these creatures….they’ll just delay the extinction and draw out the pain and torture these animals face.

These days scientists are trying to revive the Caspian tiger species by cloning them using previously-collected DNA. But, there’s no guarantee this will work. That’s why it’s important that something is done to ensure that other tiger species don’t go this route.

Caspian tiger (Source)

 

Bramble Cay melomys

The last animal on our list happens to be the very first animal to have become extinct directly as a result of climate change. Bramble Cay melomys are also the latest mammals to go extinct – having died out in 2016.

Living on the Torres Strait of the Great Barrier Reef just a few years ago, Bramble Cay melomys are now dust and bones, relics in Australia’s natural history museums.

This tiny brown rat was named after its choice of accommodation. Living in cays (which are low-lying banks, corals, rocks and other water-facing spaces on islands), this rodent species was endemic to the vegetated coral of Bramble Cay.

Increasing temperatures around the world have for long led to accelerated melting of polar ice. This has resulted in the rise of water levels in oceans around the world. As a result, the low-lying homes of the Bramble Cay melomys were flooded, drowning large populations and forcing the remaining out of their homes and into the open, where predators stalked.

Following the failed efforts by the Australian Government to trap a few melomys and re-populate the species, the animals fell victim to climate change.

Bramble Cay Melomy (Source) 

 

We need to step up and do something about this now

As of today, countless species have gone extinct. Each of these animals and birds had something unique to offer the world. But we won’t ever get to see them or share this planet with them, because of our own mistakes, greed and indifference.

As the Covid-19 pandemic has shown, just stepping away from our normal routines for a few weeks can allow nature to course-correct and put things right.

Carbon emissions have reduced worldwide. As a result, global temperatures have stabilized. Sea ice isn’t melting as fast as it used to and the ozone layer isn’t depleting at such a fast rate, as in the past.

Animals who were driven away from their original feeding or mating or birthing grounds are finally returning home. Everything has started to come full circle as the Earth has begun healing itself.

But, we don’t need the threat of the coronavirus to replicate these environmental benefits. All we need to do is make conscious decisions about the way we live. Doing so can go a long way in ensuring that the animals that are alive today, don’t just become names we tick-off on a future list of extinct animals.

 

-NISHA PRAKASH 

P.S: Featured image: Crying Earth 

What’s In A Name: The Colourful (& Sometimes Hurtful) Profession of Naming New Species

Elephas maximus borneensis, Funambulus palmarum, Ajaja ajaja, Oryza rufipogon…you may have come across these or something similar in your biology textbook or an article about wildlife. They are scientific names of animals & plants – Borneo elephant, Indian palm squirrel, Spoonbills and Wild rice, in that order.

At first read, we may not really decipher which species the name refers to. But when we do, we are pleasantly surprised.

One of the most exciting activities in the scientific community, is taxonomy – the science of grouping a newly discovered species. A part of this job involves naming the species.

While enjoyable, the process of naming a new species is also a very complicated task; which involves a lot of research, word play and sarcasm. If you’ve ever wanted to know how plants & animals get their scientific names, you’re at the right place.

 

Source: Pixabay

 

The rules of naming

The International Code of Zoological Nomenclature is the governing body which has complete control over all things taxonomy. It is the Code which spells out how an animal can be named and what rules must be followed while naming.

According to the Code, there are 3 cardinal rules that all taxonomists need to follow when naming an animal:

• Don’t use a used name – The name must be completely unique.
• Don’t be insulting – The name must not be rude to anyone.
• Don’t name the species after yourself – The final name cannot include the name of the taxonomist.

Sounds simple enough? Unfortunately it isn’t.

There are many cases in the past when scientists named an animal to either gain recognition or to take a dig at a competitor.

There was Dr. May Berenbaum, the VP of Entomological Society of America, who named a species of urea-eating cockroach after herself – Xestoblatta berenbaumae. Of course, she did say that fame wasn’t her focus when she did this. Dr. Berenbaum was already a highly-reputed scientist in the community and she only wanted to showcase her passion for creepy crawlies by naming one after herself.

 

Xestoblatta berenbaumae (Source)

 

Then there was famed 1700s botanist, the Father of Taxonomy, Carl Linnaeus. He is renowned today, not just for his contribution to taxonomy, but also for being unbelievably petty and mean towards people he didn’t like. At the height of his career, he used fellow botanist and friend Johann Georg Siegesbeck’s name as inspiration to name a foul-smelling genus of weed – Sigesbeckia orientalis – after Siegesbeck publicly criticised Linnaeus’ method of species classification. This, many believe, was meant to be a dig at Siegesbeck’s  jealousy at Linnaeus’ success.  

 

Carl Linnaeus, the Father of Taxonomy (Source)

 

Sigesbeckia orientalis aka St. Paul’s Wort (Source)

 

And who can forget Daniel Rolander, Linnaeus’ most-hated protégé?  After Rolander refused to share his field study results and samples from his trip to Suriname with Linnaeus, the latter promptly went ahead and got him banned from leading scientific and academic institutions of the time. To add salt to injury, Linnaeus also named a type of dung beetle – Aphanus rolandri – after Rolander. Ouch. 

Loosely translated to English, Aphanus rolandri means “inconspicuous Rolander”. Now that’s what I call a double whammy.

 

Aphanus rolandri (Source)

 

Here’s one more – Famed palaeontologist O.A. Peterson named a species of prehistoric pig as Dinohyus hollandi, after Director of Carnegie Museum of Natural History W.J. Holland, for the latter’s annoying habit of hogging the limelight. Holland was known in scientific circles for taking credit for every research paper published by his students, irrespective of whether he contributed to it or not.

 

Fossil of Dinohyus hollandi

Representative reconstruction

 

Okay back to the rules of taxonomy

Barring these and a few other instances of inspired, but hurtful name-calling, taxonomy has for the most period, been a civilised affair.

When naming an animal or a plant, taxonomists are told to consider the specialty of the species as inspiration. So, when scientists found a new genus of tiny sea snails, they named them Ittibittium; given how they were much smaller in size compared to another genus of sea snails – Bittium.

 

Genus Ittibittium (Source)

 

The second way to name a new species – find another creature that looks exactly like it and name the new species after that. Enter Scaptia beyonceae, a species of horse fly which is renowned for possessing a giant, golden bottom. Who else in the animal kingdom had such a big, tanned, booty? Why, Beyoncé of course.

 

Scaptia beyonceae & Beyoncé (Source)

 

TV shows and story book characters have inspired species names too. A newly discovered species of jellyfish was named Bazinga reiki after The Big Bang Theory’s protagonist Sheldon Cooper’s famous catchphrase “Bazinga”. The bacteria genus Midichloria was named after a fictional alien species called “midichlorians” described in the cult classic Star Wars.  Then there’s the fossil of a large turtle, discovered in 1992 – Ninjemys oweni, named after the hit show Teenage Mutant Ninja Turtles.

 

Bazinga reiki jellyfish

Bacteria genus Midichloria

Fossil of Ninjemys oweni

 

So, to encapsulate

Scientific names must be unique, kind, not self-glorifying and clever. They must take inspiration from the species itself or another, just like it.

Can only scientists name a new species?

Although scientists who discover the species usually get the honour of naming them, some scientists allow members of the public to send their suggestions.

In 2000, Dr Nerida Wilson discovered a species of nudibranch in the Indian ocean. She didn’t have a name for the animal. So, she decided to let the people decide. She invited names from the public and the submissions were reviewed by a panel of expert taxonomists. Finally, the entry by Patrick from New South Wales was chosen and the nudibranch was named – Moridilla fifo.

 

Moridilla fifo (Source)

 

Oh yes, here’s something else…

The names don’t need to be in Latin.

Although Latin was the language of taxonomy in the 1700s, today, there’s no strict rule requiring taxonomists to name species in Latin or Greek. You can provide a name in any language of your choice and taxonomists will tweak the spelling to resemble Latin or Greek, without actually changing or translating the name itself.

Want to name a species yourself?

Go on and keep your eyes peeled for opportunities. Who knows, the next big discovery could be named by you.

 

 

-NISHA PRAKASH

 

PS: Featured image: Hierarchy in taxonomy , Dinohyus hollandi – Fossil; Representative image, Bazinga reiki, Midichloria, Ninjemys oweni 

Humans aren’t the Only Ones Who Have Oral Sex, Other Animals Do It Too

It was a warm summer’s day in 2013 when scientists researching fruit bats in Southern India noticed a unique behaviour in their subjects. The bats – who lived in an old fig tree in the village of Malumichampatti in Tamil Nadu – were performing oral sex on their mates!

This was a startling revelation to the scientists. Till date, this behaviour hadn’t been noticed in Indian fruit bats. Up until then, it was only observed in Chinese fruit bats, but no other bat species. This discovery was new and exciting.

Only a human experience?

Humans have for long indulged in oral sex. Myths and ancient books from around the world mention oral sex aka. fellatio (oral sex on males) and cunnilingus (oral sex on females), in various capacities.

There was the Egyptian Goddess Isis, who blew life into her husband Osiris’s body by sucking on his penis, after he was murdered by his brother Set. In the ancient Indian book of Kamasutra, there is an entire chapter dedicated to the use of aupariṣṭhaka (the art of oral sex) in love making. In the ancient city of Pompeii, archaeologists unearthed baths predating 79 AD, with wall paintings of couples engaging in oral sex. 

The ancient fresco on the walls of Pompeii’s public bath. (Source)

Based on these evidences, scientists assumed that oral sex was the domain of human pleasure. That is until they found other animals engaging in it too.

Non-penetrative sex for non-humans

Animals have evolved to have sex. This includes both penetrative and non-penetrative sex.

Pet dogs and cats are excellent examples of animals which engage in non-penetrative sexual behaviours – chair mounting, dry humping and self-stimulation (auto-fellatio). In farms, the same behaviour can be observed in horses and birds The same is true of wild animals like turtles, walruses and monkeys (amongst others), who indulge in self-love.

With masturbation on the table, oral sex doesn’t seem too-far-off a possibility.

Animals like fruit flies, squirrels, bonobos, wolves, brown bears, sheep, Dunnock birds and Darwin’s bark spiders have been observed engaging in oral sex. The reason for this isn’t clear yet, although there are a few theories:

Theory #1: Oral sex can help prolong sexual activity

With the Indian fruit bats, scientists noticed that oral sex served to increase the time bats spent performing penetrative sex. The male bats would begin mating, with about 50 seconds of oral sex, followed by 10-20 seconds of penetrative sex. They would then revert to about 90 seconds of oral sex and finally back to penetrative sex of much longer duration.

This has led to conjectures regarding the connection between oral sex and the length of penetrative sex.

A Dunnock bird. (Source)

Theory #2: Oral sex can remove bad bacteria from the vagina

The second theory proposed by researchers talks of the role of oral sex in animal health.

Some scientists believe that enzymes in the animal’s saliva can remove (and sometimes kill) bad bacteria, which live on/inside the mate’s sexual organs. This was one of the theories suggested regarding the Indian fruit bats from Tamil Nadu.

Another related theory suggests that cunnilingus, may be used by males to wipe-off sperms by competitors; thereby ensuring that only their sperms successfully take root. This is the theory used to explain the behaviour of Dunnock birds; where the male pecks at the female’s cloaca until older sperm masses drop out of her body. He mates with her only after this pre-copulatory display. This he does, it is believed, to prevent his mate from mothering another male’s brood.

Theory #3: Oral sex can improve the quality and mobility of the sperm

Another theory surrounding animal oral sex is that of sperm quality. It is assumed that fellatio may remove old, ineffective sperm and allow the male to use fresh, healthy sperm when mating.

Oral sex has also been presumed to improve the mobility of sperm, allowing the sperm to travel farther through the female’s reproductive tract and ensuring a successful pregnancy.

On this note, scientists have suggested that oral sex may work the other way too – make the female more receptive to mate, by stimulating the production of natural lubrication in the reproductive tract. In fact, this theory has been suggested regarding human females too.

Theory #4: Oral sex doesn’t serve any purpose, except pleasure

Finally, the last theory considers pleasure as the only purpose for the presence of oral sex in the sexual repertoire of non-human animals.

There are many animals like bonobos and macaques, who have been observed experiencing true pleasure during sex. They engage in play during the sexual act. For these few animals, mating doesn’t serve a reproductive purpose alone. They have sex because they like it.

Some scientists believe that in these species, oral sex may only be a tool to increase pleasure; and nothing more. A lot like in humans.

A Bonobo troop. (Source)

Oral sex and homosexuality in the animal kingdom

When talking about the sexual behaviours of animals, the question does arise – is oral sex in non-human animals restricted to heterosexual mates or does it include homosexual mates too (given how oral sex is common to both heterosexual and homosexual couples in humans)?

The answer – its species-dependent.

Primates like bonobos and macaques have been observed engaging in both heterosexual and homosexual behaviours, which includes oral sex. Other animals like dolphins, who are reputed for their varied sexual antics, have been observed engaging in homosexual behaviour, but not oral sex in particular. 

This makes it very hard to define whether there is any connection between oral sex and sexuality the animal kingdom or not; or if like humans, there is absolutely no connection. 

Understanding animal sexuality

With greater awareness, scientists are slowly peeling-back the layers surrounding animal sexuality. We are learning more today about sex, reproduction and pleasure, than we ever did before.

Understanding sexuality in the animal kingdom is also helping us understand human sexuality better. It is allowing scientists to understand human physiology and human evolution better too.

Studies like these are doing one other thing – redefining what it means to be human and what it means to be animal. As the lines dividing humans from animals blurs, we may need to rethink much about ourselves and the world.  

 

 

-NISHA PRAKASH

 

P.S: Featured image: Greater Indian fruit bat.

Yes, Cold Blooded Creatures Get Fevers Too: Here’s What You Need To Know

What do amphibians, reptiles and fish have in common? They are all ectotherms – cold blooded creatures. They are animals which cannot regulate their own body temperatures (like warm blooded animals can) and they rely on the external environment to change their internal temperatures. 

For long scientists wondered if sickness like cold, flu and fever were the lot of warm blooded creatures . As it turns out – they aren’t. Cold blooded creatures can fall ill too. 

How (?), you may ask. In order to understand this, we need to understand how fevers set in warm blooded creatures. 

All warm blooded creatures have a particular body temperature, which for them is considered normal. For example: 

• Humans – 98.6°F
• Dogs – 102.0°F
• Elephants – 97.7°F
• Horses – 100.4°F
• Goats – 103.4°F

If the body temperatures of these animals rises above this limit (as is the case during infections), the body tries to thermoregulate .i.e. bring the temperature back down, to normal. When the body fails to do this and the body temperature continues to rise, fever sets in. 

 

Cold blooded animals – representative image (Image source: Pixabay)

 

What about cold blooded animals?

Based on this, it’s important to note that for fever to set in, there has to be a biologically-set body temperature. But cold blooded animals don’t have a fixed temperature. Their body temperature falls or rises depending on the temperature of the external environment. 

So, how do they fall ill?

Well, cold blooded or warm blooded, all animals are susceptible to illness. Just as with their warm blooded cousins, cold blooded animals too may get infections from parasites or viruses, which can raise or drop their body temperatures abnormally. Just like warm blooded animals, ectotherm animals’ bodies too can handle only a certain level of heat and cold. If the change in temperature during the infection falls beyond this limit, illness similar to fever sets in. 

But the biggest mystery here isn’t just about how these animals fall ill, but it also includes what these animals do to get back to health. 

Changing behaviours for the sake of wellness

When fish, amphibians or reptiles fall ill, they indulge in what is known as a “behavioural fever“. If the animal is infected by a parasite or virus and experiences signs of ill health, it moves away towards areas which support warmer climates. For example, fish that normally prefer cold waters may swim towards warmer waters when they are ill. 

Why? 

Heat has the ability to deactivate viruses and destroy the proteins which assist in virus duplication. The same goes with parasites – heat can kill them too. 

So, a cold blooded creature that falls ill, will instinctively move towards a warmer place, in order to increase its body temperature, which will in turn help in killing or deactivating the pathogen in their bodies. 

 

Zebrafish (Image source: Imperial College London)

 

This instinctive “behaviour“, which ectotherms exhibit when they have “fevers“, is called “behavioural fever“.  Scientists speculate this behaviour could stem from the fact that the immune systems of cold blooded animals may actually function better when in warmer climates.

One of the best examples of cold blooded creatures who exhibit behavioural fever are Zebrafish. The moment they fall ill, Zebra fish will change their water-heat preferences and swim to warmer waters. The same goes for Guppies. 

When behavioural fever benefits the host 

For some time, it was assumed that behavioural fever was helpful only for ectotherms who were in the throes of infection & fever. But as it turns out, in some cases, the move to hotter areas benefits pathogens too. 

Schistocephalus solidus, a tapeworm found in the gut of  rodents, fish and fish-eating birds, actually thrive on heat. Once the parasite is in the hot climate, it grows stronger and changes the heat preferences of the fish and manipulate other atypical (and often self-destructive) behaviours in the animal. 

 

Virus (Image source: Pixabay)

 

Then there is the Cyprinid herpesvirus 3, which is a virus that attacks fish in the Carp family. This virus affects the genetic code of the fish it infects and overrides the genes which stimulate behavioural fever. So, the infected fish doesn’t move towards warmer waters (as it is supposed to), instead choosing to stay in colder waters, where the virus can gain in strength. 

What happens if a feverish ectotherm cannot move to warmer climates? 

Vicious parasites and mind-control viruses aside, the inability to indulge in behavioural fever can have a massive, negative impact on cold blooded animals. This is in fact, very true of pets.

In the wild, cold blooded creatures have a lot of freedom to move to different places, in order to rid themselves of their illness and infection.  But pets stuck in aquariums and enclosures don’t have this luxury. 

Cold blooded pets like fish, turtles, tortoises, iguanas, lizards and snakes are cooped up inside their temperature-controlled tanks/enclosures for almost their entire lives; where they are subjected to the same temperature day-in-and-day-out. 

 

Caged animal – representative image (Image source: Pixabay)

 

Now imagine these pets fall ill and have a fever. Biologically they are programmed to leave and move to a place that is warmer, to heal themselves. But because they are stuck in their tanks/enclosures, these animals do not get the opportunity to get their bodies at the right temperature to kill the infection. 

When this happens, the fever and the infection only gets worse and in the worst cases, the pet dies. In fact, a large number of fish deaths in aquariums can be attributed to this.

So, what can pet owners do about this? 

Fish owners can set aside a separate tank where they can change the temperature of the water as required. Owners of amphibians and reptiles can create heat spots in corners of the enclosure by using detachable heaters and small light sources. This can give the sick pet an opportunity to self-heal. 

If however, your pet looks worse, it’s best to take him/her to a vet immediately. 

 

 

-NISHA PRAKASH 

P.S: Featured image: Iguana (Source: Pixabay)

Geckos are Weird, but Awesome: Here are 3 Reasons Why

Most of us don’t like geckos. They’re creepy little buggers who skulk in bathroom corners and whose bulging eyes look like they’re staring into your very soul. A little unnerving, to be honest.

But did you know that geckos are some of the most ingenious creatures in the world? In fact, they’re responsible for being the muse behind some of the world’s most brilliant technologies.

Scientists today have begun full-fledged studies into these slippery critters, in the hope of finding more technological inspiration from them. Here are three amazing and weird facts about them:

• They take a bath in dewdrops

Dewdrops are formed when the surface of a plant or insect’s body is hydrophobic .i.e. repels water. As it turns out, geckos have a similar, if not the same, hydrophobic skin. Gecko skin contains tiny hair-like spines which trap air from the atmosphere. When this layer of air cools down, it becomes water.

As time passes and more air collects on the hair particles, the water droplets grow in size. When they’re large enough, they are able to be manipulated by external forces like wind and gravity. A slight gust of wind or the gecko moving can make the dewdrop slide right-off its body. When the dewdrops fall-off the gecko, they clean away dirt particles on the body. This technique is extremely useful for geckos, given how many species live in dry and arid wastelands where little water is available. This type of water retention can help them stay clean and healthy, without having to look for water resources.

Here’s another fun fact. Geckos are the first vertebrates to be found possessing hydrophobic skin. Their skin has now inspired scientists to develop super-hydrophobic clothing which can self-clean by collecting water vapour from the air and which wouldn’t need washing, ever!

 

Source: National Geographic

 

• Their tails spin a tale of their own when chopped-off

Geckos, just like other lizards, have the ability to voluntarily cut-off and drop their tails when faced with danger. This defensive technique gives them the opportunity to escape. Think about it. You’re about to catch a sweet-looking gecko, when BAM!, its tail falls off. Shocking isn’t it? You probably wouldn’t want to touch it after this.

But the interesting part isn’t this ingenious tail-dropping strategy. Studies show that gecko tails can move independently in and of themselves for up to 30 minutes after they fall off. Researchers from the University of California and the University of Calgary collaborated on a project in 2009, to understand how these tail movements are controlled after the tail falls off.

The scientists pinched the base of a gecko’s tail and made it fall off. They then attached four electrodes to both sides of the tail – two on each side. They found that once the tails fell off, they began to swing from side to side. This was an automatic response. But the moment the tail was lightly-shocked through the electrodes, it started jumping and somersaulting in the air erratically.

As it turns out, gecko tails have brains of their own. The moment a predator so much as grazes against it, the tail starts jumping and flipping. A few seconds later, it goes back to its serene swinging movement. If the predator touches the tail again, it explodes into a series of complex back spins, flips and jumps.

Scientists believe this technique is an additional measure to alarm predators and keep them occupied while the gecko escapes.

 

Source: National Geographic

 

• They can right themselves mid-air just like cats

While felines have the credit for being the most aerially acrobatic of all vertebrates, it’s the geckos who have truly opened science’s eyes to amazing possibilities. Until someone observed the unique way in which geckos flipped mid-air to stop their drops, no one knew these little lizards were capable of mid-air antics.

Experiments have shown that when geckos walk on non-slippery surfaces, their tails are held high up, away from the floor and pointing towards the sky. If the ground/wall is slippery, the gecko lowers the tail to the floor and leans its body against it for support – kind of like on a fifth leg.

When geckos slip and fall, they rotate their tails at a right angle to their body. Then they twist their tails again in the same direction, to make their bodies rotate too. They basically use the momentum generated by their tails to turn right-side up, to land on their feet.

This technique ensures that geckos always land on their stomach, irrespective of the direction their bodies were in when their fall began. This entire process of turning right-side-up takes only about 100 milliseconds! Now that’s what I call fast.

For comparison, cats don’t use their tails to land on their feet when they fall. They have a very flexible backbone and free-floating collarbones which give them the flexibility and speed to twist their bodies up to 180 degrees in seconds.

 

 

-NISHA PRAKASH

 

P.S: Featured image: Gecko

 

Why Are Marsupials Found Only In Australia?

Take a look at global animal distribution and you’ll notice how each country in the world has a specific type or species of animal, that isn’t found anywhere else.

One such group of animals is the Marsupials – animals that possess a pouch which they use to raise their young in. Some of the best examples of Marsupials are kangaroos, koalas, possums and wombats.

When we think about marsupials, we always associate them with the Land Down Under. Why is it that marsupials are found only in Australia?

Okay, let’s take a moment to set the record straight. Marsupials aren’t found only in Australia. They are also found in South America, Central America and certain parts of North America & Southern Canada. The best example of an American marsupial is the Opossum. 

An opossum

Scientists believe that the first marsupials were actually born in South America and they crossed Antarctica to finally land on and inhabit Australia. This was 180 million years ago, when Australia, Antarctica and South America were a single super-continent called Gondwana. A common marsupial ancestor born in South America branched into two distinct species, with one residing in the Americas and the other migrating to Australia. Today, over 200 species of marsupials are found in Australia, 100 in South America and 13 in Central America – all descendants of the single American ancestor. 

A representative image of the ancient super-continent of Gondwana (image source)

So, the question we should be asking now is – “Why are a majority of the animals that are found in Australia, marsupial?” Or, a better question would be, “Why are so many marsupials still alive in Australia, when most of their American counterparts are extinct?” What makes Australia such a fertile ground for the birth (& survival) of so many marsupial species?. 

The answer can be two-pronged. One line of thinking states that the geography of the country-continent is the reason for a high percentage of marsupials in Australia.

Australia has been a landmass that has remained largely separate from other continents for millions of years. This meant, it was subject to weather and soil conditions that was completely different from what was found on other continents. In turn, this affected the type of plants that grew on the continent, which changed the diet of the Australian marsupials significantly from their American counterparts. The researchers who support this theory believe that the diet offered by Australia was more conducive to the development of the marsupial species as a whole, compared to the diet elsewhere.

The second theory is that, since Australia was largely and for a very long time secluded and protected from the invasion of foreign species, the marsupials of yore didn’t have much competition to face for shelter, food and water. Additionally, the predominantly marsupial population ensured the birth of more marsupials and over time, the continent was soon overrun by marsupials. 

On the other hand, the Americas blossomed with many distinct species of animals, leading to intense competition for resources and as a result, the extinction of many marsupial species. We need to remember here that marsupial babies are born underdeveloped due to the lack of a placenta. They need additional time compared to their placental or egg-born cousins to grow into strong & mature creatures. With so many threats lurking around and such few resources to be shared by thousands of animals, it was just a matter of time before the genetically-weaker marsupial species in the Americas went extinct. 

A short list of placental mammals and marsupials commonly found in the wild (image source)

The future of Australia’s marsupials

So, what’s next for our pouched friends?

Species around the world are experiencing the brunt of habitat loss and governments are implementing conservation projects to keep them safe. In Australia, the kangaroo is given protected status – with criminals found injuring or killing them, getting a one-way ticket to prison. But not all marsupials have been afforded this luxury, making conservation a challenging endeavour.

Additionally, some species like the antechinus, are going extinct for another (never-anticipated) reason – their suicidal mating tendencies – and have stumped scientists. Experts are now scrambling to save these almost-extinct species, but it may already be too late. 

In terms of whether we’ll see any new marsupial species being discovered anytime soon; only time will tell. For now, the focus is on preserving the population that is present in the Land Down Under.

 

-NISHA PRAKASH 

P.S: Featured image: Pixabay