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How do starfish and spiders digest prey outside their bodies?

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Group of fallow deer (Dama dama) stags with large, palmate antlers standing alert in a green summer field. — Animal The fallow deer (*Dama dama*) has been introduced in many areas ever since the Neolithic Period.

Spiders and starfish (asteroids) utilize external digestion to process their prey, though they employ different mechanisms to achieve this.

Spiders

Spiders digest their prey preorally, meaning digestion occurs outside the mouth. After capturing prey, spiders typically bite it using their fangs (chelicerae) to inject poison. They then pump digestive enzymes into the prey's body, which liquefies the internal tissues. Once the tissues are broken down, the spider sucks up the resulting nutrient-rich fluid. In some cases, spiders may also chew their prey while simultaneously covering it with these secreted enzymes.12

Starfish

Certain species of starfish (asteroids) are active predators that feed on shellfish and other organisms. When feeding, these starfish extrude their stomach through their mouth and onto the prey. This allows the starfish to begin the process of digestion externally. Once the prey has been partially digested outside the body, the starfish retracts its stomach, and the remaining digestive process is completed internally.3

It is important to recognize that these specialized feeding behaviors are essential adaptations for these organisms to survive and thrive in their respective environments.