Olsen Trine Bottos, Christensen Frederik Ekholm Gaardsted, Lundgreen Kim, Dunn Paul H, Levitis Daniel A
Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark; and.
Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark; and Max-Planck Odense Center on the Biodemography of Aging, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark.
Biol Bull. 2015 Apr;228(2):156-62. doi: 10.1086/BBLv228n2p156.
Echinoderms have excellent healing and regeneration abilities, but little is known about how they deal with the related challenge of durable foreign bodies that become lodged within their bodies. Here we report a novel mechanism for foreign body elimination in starfish. When injected into the arm of a starfish, passive integrated transponder tags and magnets of similar dimensions are eliminated at a rate approximating 10% per day. These objects are forcefully ejected through the body wall at the distal tip of an arm. Ultrasound images reveal that foreign bodies are moved within the body cavity, and tracking of magnets injected into starfish suggests that the movements are haphazard rather than directed. Constrictions of the body wall near the foreign object are the likely mechanism for this transport process. Open questions include the ecological relevance of this behavior, why clearance occurs through the distal tips of the arms, the neurological and muscular control of this behavior, what other animals use this mechanism, and the range of objects starfish can eliminate in this way.
棘皮动物具有出色的愈合和再生能力，但对于它们如何应对体内留存的持久性异物这一相关挑战，人们却知之甚少。在此，我们报告海星清除异物的一种新机制。当将无源集成应答器标签和尺寸相似的磁体注入海星的腕臂时，它们以每天约10%的速率被清除。这些物体通过腕臂末端的体壁被强力排出。超声图像显示异物在体腔内移动，对注入海星体内的磁体进行追踪表明，这些移动是随机的而非定向的。异物附近体壁的收缩可能是这一运输过程的机制。尚未解决的问题包括这种行为的生态相关性、为何通过腕臂末端进行清除、这种行为的神经和肌肉控制、还有哪些其他动物采用这种机制，以及海星能够以此方式清除的物体范围。
