Which Animal is a Living Fossil?
Living Fossils, a term coined by Charles Darwin for living creatures that have undergone the test of eternity - strong and pliant organisms that have survived for millions of years unchanged. Characteristics defining Living Fossils includes (a) no extinction, (b) no production of many new species (i.e. low taxonomic diversity), and (c) relatively no change over the course of millennia.
We present you some of the most unbelievable examples of living fossils.
1. Horseshoe Crabs: Appeared in the late Ordovician period some 450 million years ago and can still be seen crawling in muddy ocean floors. In spite of surviving a number of mass extinctions, their numbers stared failing because of habitat destruction in Japan and overharvesting along the east coast of North America.
2. Crocodiles: Descendants of marine super-predators, they made their first dreaded appearance around 55 million years ago. Saltwater crocodiles are the largest of living reptiles and are the largest terrestrial apex predators in the world.
3. Coelacanths: Rediscovered in 1938 off the coast of South Africa, theirunique features includes a rostral organ in the snout that’s part of its electro sensory system, and an intracranial joint in the skull that allows the anterior portion of the cranium to swing upwards, greatly enlarging the gape of the mouth.
4. Elephant Sharks: Found in the waters of Australia and New Zealand, they belong to a branch of cartilaginous fish known as chimaeras. Their DNA hardly changed for nearly 420 million years.
5. Red panda: Belonging to the temperate forests of the Himalayas, they are the only surviving members of the family Ailuridae. They symbolize a lineage that more strongly marks a cross section of bears and skunks, weasels and raccoons.
6. Purple frog: Discovered in 2003, these living fossils are described as a "bloated doughnut with stubby legs and a pointy snout." Though found in India, theirnext living relatives can only be found on the Seychelles islands.
Post Written By - Bahana Saikia
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