Sunday, 15 July 2012

Nature’s greatest illusionists

Tom Stubbs

Camouflage is one of nature’s greatest inventions. It is a mode of concealment that allows animals to remain unnoticed and blend into their environment, increasing the animal’s chances of survival. There are many common examples of camouflage, including leopard's spots and zebra's stripes. Mechanisms that increase survival and reproductive rates are strongly selected for by natural selection, this has led to the evolution of some amazing methods of camouflage that you may be less familiar with. Here we explore just a few exceptional animals that are masters of deception.

The Dead Leaf Mantis 
Dead-Leaf mimics
The Dead Leaf Mantis (Deroplatys desiccata) is a large mantis found in Malaysia. If you haven’t guessed already, it is camouflaged as a dead leaf. It achieves this using a large shield on its back, the prothorax, that is covered with a variety of colours and spots. When threatened they lie motionless in the leaf litter. This is an excellent example of crypsis. Believe it or not many people keep this species as a pet, check out the video at the bottom. While we are on the topic of dead leaves, there is also the Dead-Leaf Butterfly (Kallima inachus). It has a diet of plants and rotting fruit so it spends a great deal of time resting within the leaf litter of tropical forests. Depending on the environmental conditions the butterfly can mimic variable degrees of decay.

Orchid Mimic Mantis 
Orchid mimics
If you prefer your plants alive, then there is also the beautiful orchid mimic mantis (Hymenopus coronatus). This incredible animal uses legs that resemble flower petals to remain hidden on orchids. They can be found in rainforests of Sumatra, Indonesia and Malaysia. Many varieties of such orchid mimics are white, but some are wonderfully colourful. They are carnivorous so as well as helping them to avoid trouble this camouflage also helps the mantis capture a wide range of flying insects and small lizards. It also has the ability to change colours on a daily basis.

Sea dragons
Amazing examples of camouflage are not just found in creepy crawlies and are not just on land. There is also the Leafy Sea Dragon (Phycodurus eques).This animal is a fish belonging to the family including sea horses. It is one of the most ornamented camouflaged creatures on the planet. They possess large bodies and leaf-like appendages over their entire body, allowing them to blend in with seaweed and kelp formations. The leaves are for camouflage only and don’t help with movement. Sea dragons are endemic to the oceans of south and east Australia and feed upon tiny crustaceans such as sea lice. Again their beauty has made them popular pets and they are taken from the wild illegally.
Leafy Sea Dragon

Leaf-tailed gecko 
Leaf-tailed gecko
Reptiles have also mastered the art of disguise. The leaf-tailed gecko (Uroplatus sikorae) is one of the best examples of this. The critter is found only in the tropical forests of Madagascar and a few nearby landmasses. They have evolved moss and bark coloured scales in addition to dermal flaps that disrupt their outline. When they lay flat this cryptic colouration makes them perfectly match the branches of tropical trees when basking during the day. Like chameleons, these reptiles can also modify their colouration according to their surroundings.

More information and great videos -