All articles tagged with #parasitism
Remoras, long seen as mutualistic hitchhikers that clean and shield their hosts, may be more parasitic than previously thought. New research notes reduced grazing by hosts with remoras present and rare cases of remoras entering manta rays’ cloacae, a behavior dubbed “cloacal diving” that challenges the traditional view of a beneficial relationship and highlights the parasite-like potential of these clingy fish.
A new study documents remoras diving into manta ray cloacas and attaching beneath gill slits across manta species, suggesting these hitchhikers may be more invasive than previously thought. While remoras can help by cleaning parasites, their aggressive attachment can increase drag and cause injuries, pushing the relationship along a spectrum from mutualism to parasitism and raising concerns for manta rays already facing threats from fishing, habitat loss, and climate change. Researchers emphasize the interaction is nuanced and context-dependent, potentially beneficial in some cases and costly in others.
Earth.com reports that Anelasma squalicola, a barnacle, has evolved into a parasite that pierces lantern sharks in Norway's Sognefjord, feeding directly from host tissue and marking a rare evolutionary shift from plankton-feeding to a blood/tissue-feeding lifestyle. The finding provides a living snapshot of dramatic biological change and raises questions about whether this parasitic relationship could spread to other oceans beyond the fjord.