Spermle

Spermle is a fictional term used in speculative biology and science fiction to describe a hypothetical, minimal cell derived from a spermatozoon. It is not a recognized organism or entity in biology; the concept appears in thought experiments and narrative contexts to explore ideas about the origin of life, cellular minimalism, and reproductive biology.

In many depictions, a spermle is envisioned as a compact, mobile cell-like unit with a stripped-down set of cellular components and a basic energy metabolism. It is often portrayed possessing a small genome or genetic material and a means of propulsion, such as a flagellum, while lacking the complexity of fully developed cellular life. The term is used as a demonstrative tool rather than as a report of reality.

Academic and educational discussions use the term to probe questions about minimal viable cells, the distinction between gametes and organisms, and the feasibility of constructing life from simplified building blocks. It is also used to illustrate ethical and biosafety considerations in synthetic biology and genome minimization.

In real-world science, there is no evidence for real spermle organisms. The term does not appear in peer-reviewed literature or taxonomic databases. Related concepts include protocells, synthetic cells, minimal genomes, and studies of sperm structure and function.