Echinoderms • Spiny-skinned • Sea Star (Starfish) • Green Sea Urchin • Rosy Feather Star • Echinoderms are animals with no: brain, eyes, heart, or lungs • Water-vascular system
Habitat • Deep sea • Brackish water • Half fresh and half salt water • Substratum • Non-living material where a living organism lives or grows
Role in the Ecosystem • Skin gills • Oxygen in Carbon Dioxide out
Eaters • Carnivorous- meat eater • Omnivorous-both meat and plant eater
Bilateral Symmetry • Radial Symmetry • Pentamerous Symmetry (Sea stars and Brittle stars)- not immediately obvious at first, but later notice.
Integumentary System • Spiny-skinned • Skin-gills • Spines • Pedicelarias
Skeletal system • Calcareous spines • Endoskeleton • Calcareous plates
Locomotion Feather Stars Sea Stars and Sea Urchins • Water Vasculatory system • Sieve pate (Madreporite) • Stone Canal (Careous ring) • Ring Canals • Radial Canals • Ampulla • Tube feet • Unison
Circulatory system • Water vasculatory system • Coelom • Cilia • Gaseous exchange .
Respiratory System • Skin gills • Between calcareous plates • Ingress and egress • Oxygen • Carbon Dioxide • Diffusion • coelomic fluid • carbon dioxide
Digestive & Excretory system • Excretion • Coelomic fluid • Ameboid cells • Nitrogenous wastes • Skin gills
Nervous system • Ring of nervous tissue: Nerve net • Sense organs • Pigmented eyespot • Responds to touch
Reproductive system • Sex Organs • Gonad • Gonopore • Spawn • Ovaries • Testes • Spawn in the sea
Endocrine system • Water Vasculatory System • Stone Canal • Radial Canal
Life Cycle • Spawn • Fertilization • Physicochemical changes • Blastula • Gastrula • Ectoderm • Inner endoderm • Coelom
(Continued) • Anterior coelomic sac sends a tubular outgrowth • Cilia lines this tube • Larva is bipinnaria-has bilaterally symmetrical lobes bearing ciliated bands
Human Interaction • There are some Edible Sea Urchins • Edible Parts • Ripe Eggs • Coiled Intestine • An opportunity to document the taphonomic process of Cambrian stalked echinoderms in more detail • Studies on Echinoderms provides evidence of volatile organs within gogiids.
Interview • 1. Which animal do you most enjoy studying? Why? Assuming you are asking me about echinoderms, I would say I have often enjoyed observing sea stars. In 1996-1998 I worked as a naturalist at Marine World’s aquarium and tide pool exhibit. (Marine World is now 6 Flags.) During an eight hour shift, which was spent answering questions about various species’ natural history, I had the opportunity to observe sea star mobility. They would be in one location in the wee hours of the morning and be on the other side of the tide pool by the time I left in the late afternoon. I liked watching their delicate tube feet extend and waver. I admire the strength and dexterity of the starfish as it gloms onto a mussel and pries it apart with a surprising viselike grip. What determination!
(Continued) • 2. Which species of Echinoderms do you find most interesting? Why? I adore the diversity between sea star specimens. For example, take the rough texture and squatty shape of a bat star versus the silky smoothness and elegant lines of a leather star. The amazing variety of rainbow hues on the sea stars is fascinating…purple, orange, blue spots, mud-colored, the list goes on and on. I also think it is totally unique that they can regenerate an arm, should one be “lost”.
(Continued) • 3. Fossil records helped to make Echinoderms become a well-defined and highly derived clad of metazoans. Why, exactly is this extensive amount of fossils significant? The five fold symmetry of a sea star or sea urchin is easily recognizable. Thus, when calcite skeletons are found in strata of limestone, it is easy to determine the echinoderm clad. Therefore, the numerous fossil echinoderms help scientists to see patterns of evolution.
(Continued) • 4. Why are there so many fossils of Echinoderms? The calcite parts are pretty tough and unless the fossil hunter bangs it with a hammer it will survive well as a fossil. However, after an echinoderm’s demise, its body parts can crumble apart as the musculature disintegrates. Therefore, the best looking fossils are from when the specimen was buried in strata immediately upon death. Complete fossils are rarely found, but as they say “seek and ye shall find”, and the scientists keep searching.
Bibliography • http://universe-review.ca/I10-82-starfish.jpg • http://www.infovisual.info/02/011_en.html • http://universe-review.ca/I10-82-starfish2.jpg • http://animaldiversity.ummz.umich.edu/site/resources/biodidac/crin004_009.gif/medium.jpg • http://animaldiversity.ummz.umich.edu/site/resources/Grzimek_inverts/Crinoidea/v01_id240_con_crianat.jpg/medium.jpg • http://www.cals.ncsu.edu/course/zo150/mozley/fall/seaurchinanat.jpg • http://www.geo.lsa.umich.edu/~kacey/ugrad/3-pht--echB.GIF • http://library.thinkquest.org/26153/marine/sketch/791b.jpg • http://library.thinkquest.org/26153/marine/sketch/791a.jpg • http://biology.unm.edu/ccouncil/Biology_203/Images/SimpleAnimals/cnidariaDiagram.jpeg • http://universe-review.ca/I10-82-starfish2.jpg • http://www.daviddarling.info/images/starfish_disk_and_arm.jpg
(Continued) • http://www.personal.kent.edu/~alisonjs/paleo/morph.gif • http://www.mesa.edu.au/friends/seashores/images/Urchin.jpg • http://higheredbcs.wiley.com/legacy/college/levin/0471697435/chap_tut/images/nw0262-nn.jpg • http://jwilson.coe.uga.edu/EMT668/EMAT6680.2002.Fall/Nazarewicz/7210_final_2/7210_Project/pictures/image3.gif • http://www.seaotter.com/marine/research/stronglyocentrotus/droebachiensis/pics/droebachiensis.jpg • http://www.sms.si.edu/IRLFieldGuide/images/Urchin.gif