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> Ichthyostega

Ichthyostega

author: Walter B. Myers/Novapix

reference: t-glb91-03004

Image Size 300 DPI: 42 * 28 cm

A close-up of a three foot long Late Devonian Ichthyostega 365 million years ago in what is today the Canadian Arctic. Flanking the Ichthyostega are Rhacophyton ceratangium, ancient shrubs that are thought to be one of the earliest ferns. The reddish fruit-like nodules attached to the fronds on the right are sporangia, enclosures in which spores are formed. The large tree-like trunk on the far left is the base of a young Archaeopteris. In the foreground are prehistoric arthropods--a millipede on the left and on the right cockroaches on trunk of a decaying Lycopsid. Arthropods had been walking the Earth for 40 million years before vertebrates like Ichthyostega began venturing ashore. Ichthyostega was one of the earliest tetrapods, a descendent of lobe-finned fishes and ancestor of amphibians. Ichthyostega had lungs and seven-toed limbs that allowed it to move about the shallow waters and shores of swamps and floodplains. It was among the first terrestrial vertebrates.

Keywords for this photo:

2011 - ANIMAL - ARTHROPOD - DEVONIAN - EARTH - EVOLUTION - FAUNA - FERN - FLORA - HISTORY OF EARTH - ICHTHYOSTEGA - ILLUSTRATION - INSECT - PALEOZOIC - PLANT - TREE - WATER -