Feature

The fossil record contains many examples of the interactions that occurred between organisms. Thus, Cenozoic molluscs are commonly found encrusted by bryozoans, serpulid worms and balanid barnacles; ancient scleractinian corals and echinoderms may show unusual growth patterns as a response to organisms that have embedded themselves into the host's skeleton; fossil bones can preserve indications of biting, gnawing and trampling; and ancient leaves may retain traces of bite marks and leaf miners. Other evidence of interactions may be more cryptic or difficult to interpret, none more so than the evidence of ancient parasitism.