gemmulation

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June 29, 2026

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Gemmulation is a method of asexual reproduction, primarily seen in freshwater sponges. It involves the formation of specialized structures called gemmules. These gemmules are essentially aggregates of cells, rich in stored food, enclosed within a protective outer covering. This covering is often reinforced with spicules, which are unique to the species and aid in identification.1

Gemmules allow sponges to survive unfavorable environmental conditions, such as extreme temperatures or drought. During these periods, the adult sponge may degenerate, but the gemmules remain dormant. When conditions improve, the gemmules "germinate," with cells emerging to form a new sponge. This process is analogous to hibernation or estivation in other organisms.1

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sponge
Asexual reproduction
…best known method is called gemmulation. Gemmulation begins when aggregates of cells, mostly archaeocytes, which, when they become laden with reserve food granules become isolated at the surface of a sponge and surrounded by a protective covering. These so-called “gemmules” are expelled from the adult sponge and, in some marine…
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…best known method is called gemmulation. Gemmulation begins when aggregates of cells, mostly archaeocytes, which, when they become laden with reserve food granules become isolated at the surface of a sponge and surrounded by a protective covering. These so-called “gemmules” are expelled from the adult sponge and, in some marine…
Read More