A review of the function and evolution of the cecal appendix

Area of Science:

• Evolutionary Biology
• Immunology
• Gastroenterology

Background:

• The cecal appendix, known for causing appendicitis, was historically considered vestigial.
• Emerging research suggests the appendix plays a role in immune function and gut microbiome restoration.

Purpose of the Study:

• To review the current understanding of the appendix's pathophysiology, evolution, and functions.
• To explore the appendix's role across Mammalia, challenging previous evolutionary assumptions.

Main Methods:

• Review of existing literature on appendicitis, immunology, and evolutionary biology.
• Analysis of appendiceal traits across mammalian phylogeny.

Main Results:

• The appendix has evolved independently multiple times in mammals, indicating adaptive value.
• Despite its prevalence, a single factor driving appendix evolution has not been identified.

Conclusions:

• The appendix is not merely a vestigial organ but likely possesses adaptive functions.
• The evolutionary history of the appendix is complex and multifaceted, warranting further investigation.