Why Is It That Many of the Animal Groups That

question 31

Essay

Why is it that many of the animal groups that appeared in the Cambrian period have no living relatives?

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Definitions:

Positron Emission Tomography (PET)

A medical imaging technique that uses radioactive substances to visualize and measure changes in metabolic processes, and other physiological activities in the body.

Electrical Stimulation of the Brain (ESB)

A neurological procedure that involves applying small electric currents to specific areas of the brain, used for research, therapy, or neurological interventions.

Electroencephalograph (EEG)

An electroencephalograph (EEG) is a device used to record the electrical activity of the brain through electrodes placed on the scalp.

Lateral Hypothalamus

A region in the brain known as the hunger center; it plays a significant role in promoting feeding and drinking behavior.