Question

Suppose that an invertebrate species was lost in a mass extinction caused by a sudden catastrophic event. Would the last appearance of this species in the fossil record necessarily be close to when the extinction actually occurred? Would the answer to this question differ depending on whether the species was common (abundant and widespread) or rare? Explain.

Short answer

Before the mass extinction occurred, the record of common and rare species can be found in the fossil record (fossil remains preserved within rocks) until the occurrence of a catastrophic event.

Step-by-step solution

Invertebrates

The field of zoology describes invertebrates as multicellular animal species that reside on land and water bodies (such as a river) without an internal bony skeleton.

Some common characteristics of invertebrates include multi-celled organisms, no backbone, an open circulatory system, and compound eyes.

The several invertebrates’ classification is leeches, comb jellies, sponges, insects, myriapods, starfishes, and threadworms.

Catastrophic event

The term catastrophic event refers to anatural occurrence of earth processes that negatively affect people by endangering their lives and environment.

Forest fire, tornado, mudflows, earthquake, lightning, and flood are different examples of catastrophic events.

The fossil record and mass extinction

The catastrophic events can cause a mass extinction, due to which species get vanished.The fossil record is incomplete and consists of information only about a million years before the mass extinction of species.

The fossil record does not contain the documentation of rare species that tells about their existence before the mass extinction.

Mass extinction is the cause behind the disappearance of common and rare species; fossil record comprises information about both species (common and rare species) before the mass extinction.