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Description
The molluscs are a very diverse group of animals having evolved to live succesfully in the sea, in fresh water and on land. This programme charts their evolutionary history which began with a creat...ure as small as a pinhead and led to the squids, the clams, the snails of today.
Metadata describing this Open University video programme
Module code and title: S364, Evolution
Item code: S364; 03
First transmission date: 23-04-1981
Published: 1981
Rights Statement:
Restrictions on use:
Duration: 00:24:21
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Producer: Roger Jones
Contributor: Peter Skelton
Publisher: BBC Open University
Keyword(s): Evolution; Fossils; Molluscs; Monoplacophora
Footage description: The programme opensd with a montage of molluscs. Peter Skelton introduces the programme. Skelton goes on to build a model of an archetypal mollusc in the studio. He points out the basic components common to all molluscs as he does so. As the shell of molluscs is the only thing preserved as a fossil, Skelton explains how one can determine the basic organisation of the animal's body from the shell record and from ths reconstruct the anatomy. Shots of Verna, a Monoplacophoran primitive mollusc, which is alive today but has changed very little since the Cambrian. Skelton compares this living fossil with his model of the primitive, archetypal mollusc constructed earlier in the programme. Shots of a fossilised Monoplacophoran from the Cambrian called Latouchella. Shots of fossils of a later Monoplacophoran called Pilina and of Heraultipegma, from a new sub-phylum, Cyrtosoma. Commentary by Skelton points out the evolutionary changes which occurred. Shots of fossil Eopteria, from a new class of mollusc, Rostroconchia. Shots of a fossil Fordilla from the molluscan class, Bivalvia. Commentary points out the features which distinguish this important class of molluscs from others. The programme goes on to look at evolutionary radiation of the Cyrtosomes which was more spectacular than that of the Diasomes above, shots of fossil Cyrtolite and associated muscle scars. With a model of a mollusc Sinuitopsis (a Devonian mollusc), Skelton points out the anatomical features of this animal. Shots of a fossil, Pelagiella and also of a model of this mollusc. Skelton looks at an important evolutionary event for molluscs, that of torsion. An animation shows the process of torsion and shots of fossil Aldanella, a modern snail and of a fossil Knightoconus show the results. Skelton briefly examines the evolution of the Cephalapods. Shots of cuttlefish swimming and model of a fossil cephalapod Plectronoceros from the upper Cambrian. Skelton, with the aid of the models used in the programme summarises the molluscan radiation which began in the Cambrian.
Master spool number: HOU3338
Production number: FOUS118W
Videofinder number: 2054
Available to public: no