Crab

6 Surprising Symbiotic Relationships

Photo: ShutterstockThis article was originally published by Youth Time Magazine

Photo: Shutterstock

This article was originally published by Youth Time Magazine

Can you imagine how your life might be without your best friend? Who would laugh at your terrible jokes or have your back any time you got into trouble? As humans, we rely heavily on friends for support, companionship and even when we want to kick back and have some fun. In fact, whether in social or professional spheres, it is generally accepted that forming strong bonds and partnerships with one another can often bring about positive results.

But did you know that such partnerships are also formed throughout the animal kingdom - and not just within a single species? Some creatures forge lifelong relationships with entirely different organisms in order to get through their days just a little easier. These types of alliances are known scientifically as symbiotic relationships, which can be separated into three different types: commensalism, mutualism, and parasitism.

Commensalism is a type of symbiotic relationship between two different animal species whereby only one of them benefits. The other is neither helped nor harmed. The opposite of commensalism is parasitism, which involves one organism gaining from the inter-species relationship, but to the detriment of its host. Ticks are a well-known example of a parasite. Mutualism is the win-win form of symbiotic relationships, with both partners benefiting.

Below, I will introduce you to some of the most weird and unlikely examples of symbiotic relationships within the animal kingdom.

 

Nile Crocodile and Egyptian Plover

Photos: Shutterstock

Photos: Shutterstock

The Nile crocodile is well-known for being hyper-aggressive whenever an uninvited visitor steps into their territory. However, there is one creature that the scaly reptilians will not only tolerate, but practically welcome into their aquatic domain. Incredibly, the Egyptian Plover aka “Crocodile Bird” will fly into the crocodile’s open mouth and feed upon the decomposing meat stuck between their teeth. The plover gets a not so scrumptious meal while the crocodile gets a little free dental work!


Sharks and Pilot Fish

Photo: Shutterstock

Photo: Shutterstock

Similar to the mutualistic relationship between Nile crocodiles and Egyptian plovers, many species of shark have established an unlikely alliance with pilot fish. While the pilot fish helps to rid the shark of parasites and clean away fragments of food caught between their teeth, it benefits from protection against other predators. The companionship between these two species is said to be so strong that there are even tales of distressed pilot fish following trawler vessels months after catching “their” shark.


Coyote and Badger

Photo: Shutterstock

Photo: Shutterstock

Back on to dry land and let's take a closer look at the unlikely coalition between coyotes and badgers. With speed being their main predatory tactic, coyotes usually rely on open environments to pursue and kill their prey. However, badgers are diggers, capturing their prey whilst resting in their subterranean burrows. In some parts of North America, coyotes have been observed waiting outside burrows for ground squirrels fleeing from an attacking badger. While both parties rarely benefit from any one hunt, the badger also enjoys success thanks to this unlikely relationship. Sensing the danger posed by the coyote, some animals remain in their burrows, allowing the badger a greater opportunity to catch them.


Hermit Crabs and Sea Anemones

Photo: Shutterstock

Photo: Shutterstock

Another unlikely marine pairing is that of hermit crabs and sea anemones. By poking the anemone with its pincers and holding it in place, the crab encourages it to attach to its shell. While the anemone bags itself a free ride across the seabed upon the hermit crab's back, they effectively serve as bodyguards, providing shelter and using their barbed tentacles to actively fend off hungry hermit predators.


Colombian Lesserblack Tarantula and Dotted Humming Frog

Photos: Shutterstock

Photos: Shutterstock

It might seem odd to think that a creature as sinister-looking as a tarantula could form a symbiotic relationship with an animal it could easily kill and eat. But that is exactly the case in this odd partnership between the Colombian lesserblack tarantula and dotted humming frog of South America. In fact, the large creepy crawly even allows the tiny frog to share its burrow! While the plucky little amphibian enjoys protection from fierce predators, the spider benefits from the frog devouring carnivorous ants that attack and eat the tarantula’s eggs.


Drongos and Meerkats

Photos: Shutterstock

Photos: Shutterstock

This incredible partnership between bird and mammal was made famous in the BBC wildlife documentary “Africa” hosted by the legendary David Attenborough. The drongo serves as a lookout for hunting meerkats, giving a warning cry whenever a predator is within the vicinity. Upon hearing the alarm, the spirited little mammals scuttle back to their burrows, often dropping any prey they have captured in order to speed up their escape. Most of the calls made by the drongo are genuine. However, the mischievous drongo has learned that by raising false alarms, it can swoop down and pick up a free meal dropped by a fleeing meerkat. A master of mimicry, the drongo has even been witnessed making warning calls made by meerkats!

(The Real) Fantastic Beasts and Where to Find Them - Giants

This article was originally published by Youth Time International Magazine

This article was originally published by Youth Time International Magazine

In this edition of (The Real) Fantastic Beasts and Where to Find Them we take a closer look into the giants of the natural world. From megafauna roaming Africa’s vast savannas to the creepy critters that lurk the forest undergrowth, discover more about the Goliaths of each taxonomic class and learn where to best locate them.


Largest Land Mammal: African Bush Elephant

African Bush Elephant Facts

The African Elephant has been classified into two subspecies, namely the African Bush Elephant and the African Forest Elephant. The former is the largest terrestrial animal on earth with the latter in third - after the Asian Elephant. With an average height of 3.3 metres and a mass of 6 tonnes, the African Bush Elephant towers over all others in the family. The largest elephant ever recorded was a bull (male) in Angola. He weighed in at 11 tonnes, and was nearly a meter taller than the average elephant. Due to illegal poaching for their ivory, habitat destruction, and human-wildlife conflict, elephant numbers have dwindled over the past few centuries making them vulnerable to extinction. Among the best places to witness the African Bush Elephant in its natural habitat are the Okavanga Delta, Botswana and the Addo Elephant Park in South Africa.


Largest Marine Mammal: Blue Whale

Blue Whale Facts

Not just the largest of all marine mammals, but claiming the title of largest creature ever to inhabit the Earth, the Blue Whale can grow to lengths of up to 30 metres and weigh up to 180 tonnes. Comparable in size to a small car, they have the largest heart of any animal and possess tongues that can weigh more than an elephant! Due to commercial whaling, their numbers depleted significantly throughout the 19th and 20th centuries, but their population has steadily increased since being protected worldwide from 1966. The IUCN estimates the Blue Whale population at between 10,000 – 25,000 individuals with the best chances of observing these colossal beasts off the coast of Dondra Point in Sri Lanka.


Largest Bird: Ostrich

Common Ostrich Facts

The largest of all birds by some distance, the Ostrich can grow up to 2.8 metres in height and weigh close to 145kg (that’s the weight of two average adult humans!). To add to its repertoire, they also boast the fastest land speed of any bird – reaching speeds of up to 70 km/h – and lay the largest eggs of any living bird. Furthermore, along with the largest squids in the ocean, they have the biggest eyes in the entire animal kingdom. Females tend to be about 2/3 the size of males and sport a brown/grey plumage with the males exhibiting black and white feathers. It is thought to be a camouflage technique to evade predators during breeding season whereby the female will sit on the eggs during the day, with the male taking on the responsibility at night. For the best chances of spotting them in the natural environment, head to Oudtshoorn, South Africa which has been aptly named the Ostrich capital of the world.


Largest Reptile: Saltwater Crocodile

Saltwater Crocodile Facts

The Saltwater Crocodile is a prehistoric looking reptile that is also known as the estuarine crocodile, sea crocodile, and more informally, saltie. The males grow up to sizes that far exceed that of females, typically reaching up to around 5-6 metres in length and weighing nearly a tonne. Owing to their ability to dwell in a wide range of habitats, these menacing characters have the broadest distribution of any extant crocodile species. In fact, their range spans from the eastern coast of India through to northern Australia. Well known Saltwater Crocodile hotspots include Daintree River in Far North Queensland, and Cahills Crossing, Kakadu National Park, Northern Territory – both located in Australia. Always practice extreme caution when heading out to spot these highly aggressive critters.


Largest Bony Fish: Mola Mola

Mola Mola Facts

The largest of all fishes is actually the cartilaginous whale shark, but since we’ve already covered this species in the Fantastic Beasts series, we decided to shed some spotlight on the largest of the bony fish – the Mola Mola, or, Ocean Sunfish. These odd looking marine animals are often as tall as they are long, with specimens growing up to 3.2 metres in height! The weight of mature Mola Mola can differ greatly, ranging between 250kg to a tonne. Due to the high levels of bycatch observed in many fisheries around the world, Mola Mola has been listed as vulnerable on the IUCN Red List. Their range is circumglobal and there are many operators that offer the chance to dive with Mola Mola, including those based in the Nusa Penida, Indonesia and Oban, Scotland. The Galapagos Islands are also well known for spectacular diving experiences with these gigantic ocean dwellers, among other aquatic animals.


Largest Amphibian: Chinese Giant Salamander

Chinese Giant Salamander Facts

The most vulnerable to extinction of all animals in this article and the largest of all amphibians, the Chinese Giant Salamander is considered “a living fossil”. Endemic to rocky mountain streams and lakes in China, their numbers have fallen by as much as 80% since the 1950s due to pollution, habitat loss, and use in traditional Chinese medicine. As most Chinese Giant Salamander stop feeding at water temperatures exceeding 20 °C, the species is also highly vulnerable to the effects of global warming. While they rarely reach such lengths in the present day, the Chinese Giant Salamander has been known to grow to as long as 1.8 metres and reach up to 50kg! Spotting them in the wild is a tall order, but doing so would likely happen in the basins of the Yangtze, Yellow and Pearl Rivers within China.


Largest Insect: Wētāpunga

Wetapunga Facts

Unless you’re a diehard entomologist, you probably won’t be planning a trip to spot the world’s largest insect, the wētāpunga any time soon. Endemic to the arboreal forests situated on Little Barrier Island off the coast of New Zealand, these giant crickets can reach lengths up to 7.5 cm and weigh more than a small sparrow! They are heavily predated on by birds (especially saddlebacks) and kiore rats, and in tandem with their restricted distribution this has led them to become listed as a vulnerable species on the IUCN Red List. Note that the heaviest insect in the world is the Goliath Beetle.


Largest Arachnid: Goliath Birdeater

Goliath Birdeater Facts

The Goliath Birdeater is the thing of nightmares for any sufferer or arachnophobia. These enormous blond tarantulas are largest arachnids both by size and weight but second to Laos’ giant huntsman spider by leg-span. The Goliath Birdeater boasts a body length of up to 11.9 cm and can weigh as much as 175g. Their fangs are long enough to penetrate human skin, but seldom do they attack people and when they do, it is almost always in self defence. Further, despite carrying venom it is relatively harmless to humans, comparable to that of a wasp sting. Their diet consists mainly of large arthropods, worms and amphibians, but they have been known to prey on rodents, lizards, snakes, and, as their name suggests, birds! The Goliath Birdeater lives in deep burrows found in marshy and swampy areas of the Amazon Rainforest in northern Brazil and southern Venezuela. However, you’re more likely to find this nocturnal critter dead and served as part of the local cuisine!


Largest Crustacean: Japanese Spider Crab

Japanese Spider Crab Facts

Not just the largest of all crustaceans but the biggest arthropod (insects, arachnids, myriapods, and crustaceans) that scuttles the planet, the Japanese Spider Crab can reach up to 5.5 meters from claw to claw and weigh as much as 19kg. Adults are found at depths between 50-600 meters below the water surfaces off the southern coasts of the Japanese island of Honshū, making the species very difficult to observe in the wild. In fact, the only chance you’re ever likely to encounter them in the wild is when they are unrecognizable – shortly after hatching. You may well have brushed past thousands of Japanase Spider Crabs without even knowing it if you’ve ever gone swimming in the waters off the coast of Japan!


Other Natural World Giants

  • Tallest animal: Maasai Giraffe (5.5 metres/1.2 tonnes)

  • Largest land carnivore: Polar Bear/Kodiak Bear (3 metres/450kg)

  • Largest marine carnivore: Sperm Whale (12 metres/57 tonnes)

  • Largest fish: Whale shark (12.5 metres/21.5 tonnes)

  • Largest mollusk/invertebrate: Colossal Squid (14 metres/495kg)

  • Largest wingspan: Wandering Albatross (3.65 metres)

  • Heaviest flying bird: Kori Bustard (18kg)

  • Longest marine animal: Lion’s Mane Jellyfish (55 metres)

  • Longest land animal: Reticulated Python (7.67 metres)


All photos Shutterstock. Graphics by Leigh Woods