What defines the subphylum Vertebrata?
The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. These two structures define the subphylum Vertebrata.
Questions about Vertebrate
Short answers, pulled from the story.
When did vertebrates originate during the Cambrian explosion?
Vertebrates originated approximately 518 million years ago during the Cambrian explosion. The earliest known examples belong to the Chengjiang biota and include Haikouichthys and Myllokunmingia.
How many described vertebrate species exist today according to current estimates?
Described vertebrate species total approximately 66,178 with less than five percent representing all described animal species globally. Extant species are roughly equally divided between fishes of all kinds and tetrapods.
Why have freshwater populations declined sharply since 1970?
Freshwater populations declined sharply after 1970 following land-use changes and resource exploitation. Five main causes drive biodiversity loss including habitat destruction resource extraction global warming contamination and non-native species introduction.
Who defined vertebrates as a taxonomic group distinct from invertebrates in 1801?
Jean-Baptiste Lamarck defined vertebrates as a taxonomic group distinct from invertebrates in 1801. He described them consisting of four classes: fish reptiles birds and mammals treating cephalochordates and tunicates as molluscs.