Creatures that have survived millions of years of natural selection have used many different strategies to stay alive. One of these strategies is to try and avoid detection by predators. This is achieved in many various ways. Demonstrated here are just some of those amazing organisms that managed to survive for so long.
Flap neck cameleon -(Camaeleo dilepsis)
The flap neck chameleon is renowned for its ability to change the colour of its skin. This incredible physical adaptation is made possible by cells called chromatophores of which there are three types:
- xanthophores, which contain yellow-red pigments;
- iridophores containing colourless stacks of crystals or platelets that reflect and scatter light to generate hues such as blues, white and ultra-violet
- melanophores, which contain black melanin pigment
While camouflage is often believed to be the main purpose of this stunning change, hormones, mood, temperature and breeding behaviour are what actually influence and cause a Flap Neck Chameleon to change its skin colour. Camouflage is however a secondary advantage of this change. But how does this colour change come about? In basic terms the brain controls which pigments to hide or display depending on the above-mentioned influences.
Little bittern –Xobrychus minutus
The little bittern breed amongst reed beds. Nesting on platforms of reeds in shrubs. The will lay four to eight eggs . They are very difficult to see with its skulking lifestyle and reed bed habitat. When disturbed it will freeze and stand with its neck stretched upwards and bill pointing up.
They feed on fish, insects and amphibians.
Flower mantis- https: Hymenopus coronatus and other Hymenopus spp.
Flower mantises mimic flowers to an amazing copy of the flower.This criptic coloration is an example of aggressive mimicry. This strategy of mimicry aims lure prey. They typically climb onto a plant, and then staying still until a prey insect comes within range. Rhis makes them also popular as pets. Females even lay their eggs in a very well concealed capsule called an ootheca.
It is truly amazing when one looks at these few examples of truly astonishing defense systems how these helped to keep them alive for millions of years. Maybe some of the Bushwise students will be lucky enough to see these during the course.
- Die mieliestronk ● EOL.org ● Biokids.umich.edu ● Snailworld.com ● Reptilez.com ● wikipedia * Wikimedia * ranger diaries.com
Blog by Gerhard van Niekerk