The fossil record and the early evolution of the Metazoa
Article Abstract:
Molecular biology combined with a reexamination of the fossil evidence is helping to elucidate the origin and initial evolution of the multicellular animals or Metazoa. By obtaining new ribosomal RNA data, molecular biologists are casting light on the phylogeny or evolutionary relationship between the approximately 35 known metazoan phyla. The fossils indicate that the metazoans evolved first as Ediacaran-type soft-bodied animals during the late Precambrian or Vendian Era about 600 million years ago and then diversified as triploblastic phyla during the Cambrian Era.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
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Singing and hearing in a Tertiary bushcricket
Article Abstract:
It is possible that bushcrickets evolved from a bilaterally symmetrical ancestor, according to an analysis of some very well preserved stridulatory and hearing organs of the oldest known bushcrickets from the lowermost Tertiary sediments of Denmark. The fossil wings have lower asymmetry than extant species. The fossils, from the large bushcricket Pseudotettigonia amoena, show that this bushcricket produced a broadband frequency song with a dominant frequency peak at around 7 kHz and an ultrasonic range.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1999
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Fossil record of mass moth migration
Article Abstract:
The discovery of very large numbers of lepidopteran fossils in marine, diatomous sediments of the Fur Formation from the lowermost Tertiary of Denmark is reported. It appears that mass migrations took place over the Palaeogene North Sea.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2000
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