Images: World's Oldest Petrified Sperm
Sperm Spirals
Reconstruction of 16 million-year-old giant sperm shows its coiled spiral structure.
Ostracod Anatomy
A figure showing the anatomy of an ostracod and its giant sperm, alongside microscope images of modern giant sperm bundles.
Ostracod Reconstructed
Nanotomography reconstructions of the anatomy of a female ostracod. Yellow hose-like structures are spiral ducts that lead to the seminal receptacle.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.