Why Is the Fossil Record Incomplete

question 18

Multiple Choice

Why is the fossil record incomplete?

• A) Transitional forms of organisms do not exist because evolution constantly forms new organisms from scratch.
• B) The remains of organisms form fossils by chance and are later discovered by chance.
• C) DNA evidence cannot be obtained from fossils.
• D) Evolutionary trends cannot be determined without complete skeletons, which are rare.

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Definitions:

Medullary Cavity

The central cavity of bone shafts where red and/or yellow marrow (blood cell production or fat storage, respectively) is stored; pivotal in the hemopoietic process and energy storage.

Articular Cartilage

A smooth, white tissue that covers the ends of bones where they come together to form joints, enabling low-friction movement.

Long Bones

Bones that are longer than they are wide, found in the arms, legs, hands, and feet, playing a major role in movement.

Periosteum

Surrounding the bones, apart from the joint surfaces, is a compact layer of vascular connective tissue.