Covering behavior of deep-water echinoids in Antarctica: possible response to predatory king crabs

2018

JMSE

Neuromorphic engineering is the approach to intelligent machine design inspired by nature. Here, we outline possible robotic design principles derived from the neural and motor systems of sea urchins (Echinoida). Firstly, we review the neurobiology and locomotor systems of sea urchins, with a comparative emphasis on differences to animals with a more centralized nervous system. We discuss the functioning and enervation of the tube feet, pedicellariae, and spines, including the limited autonomy of these structures. We outline the design principles behind the sea urchin nervous system. We discuss the current approaches of adapting these principles to robotics, such as sucker-like structures inspired by tube feet and a robotic adaptation of the sea urchin jaw, as well as future directions and possible limitations to using these principles in robots.

Section: Covering Behaviormentioning

confidence: 99%

Sea Urchins as an Inspiration for Robotic Designs

Stiefel

2018

JMSE

“…The sea urchins actively manipulate these debris fragments with their tube feet and combine these with their spines to transport them onto their upward facing body surface. Suggested reasons for this behavior are UV protection (demonstrated for Tripneustes gratilla [5,6]), olfactory camouflage (suggested for covering species living in light-deficient deep-sea environments [7,8], and use as a ballast for weighing down of the animal by increasing the relative density of the sea urchin in the face of currents or surge (shown for Strongylocentrotus droebachiensis [2] and for Paracentrotus lividus [9]) as well as a direct anti-predatory function [1,10]. It has been shown that sea urchins increase their coverage if faced with stressors such as UV radiation and wave action [2,6].…”

Section: Introductionmentioning

confidence: 99%

Tool Use by Four Species of Indo-Pacific Sea Urchins

Revell²,

Harding³

et al. 2019

JMSE

We compared the covering behavior of four sea urchin species, Tripneustes gratilla, Pseudoboletia maculata, Toxopneustes pileolus, and Salmacis sphaeroides found in the waters of Malapascua Island, Cebu Province and Bolinao, Panagsinan Province, Philippines. Specifically, we measured the amount and type of covering material on each sea urchin, and in several cases, the recovery of debris material after stripping the animal of its cover. We found that Tripneustes gratilla and Salmacis sphaeroides have a higher affinity for plant material, especially seagrass, compared to Pseudoboletia maculata and Toxopneustes pileolus, which prefer to cover themselves with coral rubble and other calcified material. Only in Toxopneustes pileolus did we find a significant corresponding depth-dependent decrease in total cover area, confirming previous work that covering behavior serves as a protection mechanism against UV radiation. We found no dependence of particle size on either species or size of sea urchin, but we observed that larger sea urchins generally carried more and heavier debris. We observed a transport mechanism of debris onto the echinoid body surface utilizing a combination of tube feet and spines. We compare our results to previous studies, comment on the phylogeny of sea urchin covering behavior, and discuss the interpretation of this behavior as animal tool use.

“…transport them onto their upward facing body surface. Suggested reasons for this behavior are UV protection (demonstrated for Tripneustes gratilla, (Belleza, Samuel and Jr, 2012;Ziegenhorn, 2016)), olfactory camouflage (suggested for covering species living in dark deep-sea environments, (David, Magniez and Villier, 1999;Brothers et al, 2016)) and use as a ballast for weighing down of the animal in the face of currents or surge (shown for Strongylocentrotus droebachiensis, (Dumont et al, 2007)) as well as direct anti-predatory function (Zhao, Ji, et al, 2014) (Agatsuma, 2001).…”

mentioning

confidence: 99%

Tool use by four species of Indo-Pacific sea urchins

Revell

Harding

et al. 2018

Preprint

We compared the covering behavior of four sea urchin species, Tripneustes gratilla, Pseudoboletia maculata, Toxopneutes pileolus, and Salmacis sphaeroides found in the waters of Malapascua Island, Cebu Province and Bolinao, Panagsinan Province, Philippines.Specifically, we measured the amount and type of covering material on each urchin, and, in several cases, the recovery of debris cover after stripping the animal of its cover.We found that Tripneustes gratilla and Salmacis sphaeroides have a higher preference for plant material, especially sea-grass, compared to Pseudoboletia maculata and Toxopneutes pileolus, which prefer to cover themselves with coral rubble and other calcified material. Only for Toxopneutes pileolus did we find a decrease in cover with depth, confirming previous work that the covering behavior serves UV protection. We found no dependence of particle size on either species or urchin size, but we observed that larger urchins carried more and heavier debris. We observed a transport mechanism of debris onto the echinoid body surface utilizing a combination of tube feet and spines. The transport speed of individual debris items varied between species.We compare our results to previous studies of urchin covering behavior, comment on the phylogeny of urchin covering behavior and discuss the interpretation of this behavior as animal tool use.