Sea urchins can perceive the chemistry of their predators and react instantly by changing their movement patterns.
Sea urchins can perceive the chemistry of their predators and react instantly by changing their movement patterns. Sea urchins, albeit having a limited and ancestral sensory system, can show a complex behaviour when escaping a predator. These marine invertebrates tend to move slowly and with unpredictable movements, but when they smell a predator, they escape following a ballistic motion -straightforward, quick and directional- to escape the threat. This is stated in an article now published in the journal BMC Movement Ecolog y. The first author of the study is the expert Jordi Pagès, from the Faculty of Biology and member of the Biodiversity Research Institute ( IRBio ) of the University of Barcelona, and also the CEAB-CSIC. Other co-authors of the article are the experts Javier Romero ( UB - IRBio ), Frederic Bartumeis ( CEAB-CSIC and CREAF) and Teresa Alcoverro ( CEAB-CSIC ). Sea urchins: from Brownian motion to superdiffusion The P aracentrotus lividus or sea urchin is a herbivorous animal with long and robust spines that lives in the rocky seabeds and marine phanerogamic meadows of the Mediterranean Sea and the Atlantic Ocean. It belongs to the echinoderms -a species from echinoderms without arms and slow movements- and it moves thanks to its ambulacral system, of radial symmetry and five rows of small feet with ventouses.
