Anchura, is a genus of extinct marine gastropods (snails) found as fossils only in marine deposits of Cretaceous age (between 145.5 million and 65.5 million years old). It is thus a useful guide or index fossil because it is easily recognizable. The shell whorls are globular and ornamented with raised crenulations; the spire is sharply pointed; the body whorl, the final and largest whorl, has a prominently extended outer lip. Paleontologist studying Anchura have defined different species. Which species concept was used?

Amswer:

Phylogenetic Species Concept

Explanation:

The phylogenetic species concept was introduced as an attempt to classify species based on their relativeness to other species. Instead of attempting to explain the reproductive boundaries of populations, scientists uses the phylogenetic species concept attempt to discover their genealogical relationships. A group of individuals that includes all the descendants of one common ancestor, leaving no descendants out, is called a monophyletic group.

Under this concept, a species is "a diagnosable cluster of individuals within which there is a parental pattern of ancestry and escent, beyond which there is not, and which exhibits a pattern of phylogenetic ancestry and descent among units of like kind" .

which elements do geologists measure to determine the age of an organism’s remains? check all that apply.

carbon-14

nitrogen

carbon-12