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Ray-finned fish, class Actinopterygii, differ from lobe-finned fish in that their fins consist of webs of skin supported by spines ("rays") made of bone or horn. There are other differences in respiratory and circulatory structures. Ray-finned fish normally have skeletons made from true bone, though this is not true of sturgeons and paddlefish ...
Electrophoresis testing of 14 coelacanth enzymes shows little genetic diversity between coelacanth populations. Among the fish that have been caught were about equal numbers of males and females. [8] Population estimates range from 210 individuals per population to 500 per population.
Major groups of fish evolved during this period, often referred to as the age of fish. [39] See Category:Devonian fish. D e v o n i a n: Early Devonian: Early Devonian (419–393 Ma): Psarolepis: Psarolepis (speckled scale) is a genus of extinct lobe-finned fish that lived around 397 to 418 Ma.
The evolution of tetrapods began about 400 million years ago in the Devonian Period with the earliest tetrapods evolved from lobe-finned fishes. [1] Tetrapods (under the apomorphy-based definition used on this page) are categorized as animals in the biological superclass Tetrapoda, which includes all living and extinct amphibians, reptiles, birds, and mammals.
Hardy's hypothesis as outlined in New Scientist was: . My thesis is that a branch of this primitive ape-stock was forced by competition from life in the trees to feed on the sea-shores and to hunt for food, shell fish, sea-urchins etc., in the shallow waters off the coast.
The idea of a tree of life arose from ancient notions of a ladder-like progression from lower into higher forms of life (such as in the Great Chain of Being).Early representations of "branching" phylogenetic trees include a "paleontological chart" showing the geological relationships among plants and animals in the book Elementary Geology, by Edward Hitchcock (first edition: 1840).
Fossils can then be mapped onto cladograms and range charts to assess which lineages are missing in the fossil record. [8] A classic example is the coelacanth, a type of fish related to the lungfishes and to primitive tetrapods. Coelacanths have been around for the past 80 million years but have failed to leave any fossils.
A report published by J.R. Harlan and E.B. Speaker (1969) in Iowa Fish and Fishing states that the fish weighed over 198 lb (90 kg). [18] The world record paddlefish caught on rod and reel weighed 144 lb (65 kg) and was 54.25 in (1.378 m) long. The fish was caught by Clinton Boldridge in a 5 acre pond in Atchison County, Kansas on 5 May 2004.