Oldest record of a bisexual plant
Article Abstract:
Plant fossils found in Landeyran Quarry in the French Massif Central provide the earliest evidence of bisexuality in plants. The remains of charophytes from the Devonian period show coalescent male and female gametangia. They show that the structure of the male sex organs has changed very little since that time. The female reproductive organs, or the oogonia, are found to be surrounded by ramified axes carrying the male reproductive organs, called the antheridia.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1997
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The vertebrate track record
Article Abstract:
The fossil record is incomplete, but a major tetrapod track record may fill many gaps in the distribution data of fossil vertebrates. Tracks are seen as useful to demonstrate vertebrate presence and activity, and with the maturation of vertebrate ichnology, new empirically derived questions are posed. Without consideration of the track record data, the many questions about posture, locomotion, foot morphology and locomotion cannot be fully understood.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1998
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Longevity record for deep-sea invertebrate
Article Abstract:
The ecosystem-structuring vestimentiferan tubeworm, Lamellibrachia, needs between 170 and 250 years to grow to two metres, making it the most long-lived non-colonial marin invertebrate. Growth rates and longevity were studied using nonlinear regression to fit a range of growth models. Growth was found to occur episodically.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2000
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