Arthropods (phylum Arthropoda) (from Greek ἀρθρον, meaning joint and πούς/ποδός, meaning foot) are the largest phylum of animals and include the insects, arachnids, crustaceans, and others. Approximately eighty percent of extant animal species are arthropods, with over a million modern species described and a fossil record reaching back to the early Cambrian. Arthropods are common throughout marine, freshwater, terrestrial, and even aerial environments, as well as including various symbiotic and parasitic forms. They range in size from microscopic plankton (~0.25 mm) up to forms several metres long.

Arthropods are characterised by the possession of a segmented body with appendages on each segment. They have a dorsal heart and a ventral nervous system. All arthropods are covered by a hard exoskeleton that is made out of chitin, a polysaccharide. Periodically, an arthropod sheds this covering when it moults. This covering makes arthropods less prone to dehydration.

Basic arthropod structure

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MarineBio Blog

Great white sharks hunt just like Hannibal Lecter?
David Mon, 22 Jun 2009 20:48:34 -0000
Great white sharks hunt just like Hannibal Lecter By SETH BORENSTEIN WASHINGTON (AP) — Great white sharks have some things in common with human serial killers, a new study says: They don’t attack at random, but stalk specific victims, lurking out of sight. The sharks hang back and observe from a not-too-close, not-too-far base, hunt strategically, and learn [...]
Shark Week 2009: Is Discovery Channel still demonizing sharks?
Joni Thu, 18 Jun 2009 19:45:23 -0000
Shark Week 2009 – I got an email from “WhySharksMatter” blogger David Shiffman asking for questions he should ask Discovery Channel producers about airing their infamous shark shockumentaries. At first I fully agreed with him. Yeah! Let’s tell Discovery we’re sick of the shock-docs and we want shark shows that educate us on the magnificence of [...]
Straight from the White House blog: Climate Change Impacts Across America
Joni Wed, 17 Jun 2009 04:17:09 -0000
See: http://www.whitehouse.gov/blog/Streaming-Now-Climate-Change-Impacts-Across-America-Renewed-Focus-for-Decisions/ Today, the White House helped to launch a new science report representing a consensus of 13 agencies developed over a year and half and focused on potential climate change impacts on the United States. It’s the most comprehensive report to date on the possible impacts of climate change for everyone across America, and begins an [...]
Happy World Oceans Day
David Mon, 08 Jun 2009 15:13:02 -0000
Let’s celebrate this first official World Oceans Day by recognizing the world’s 15 largest marine protected areas (MPAs) created to safeguard marine habitat around the world. Here’s the list and a bit about each one, plus some further comments and a special request below: 1. Phoenix Islands Protected Area, Kiribati (410,500 km2) — the largest MPA [...]
Shark-Free Marina Initiative to reduce worldwide shark mortality
Joni Sat, 30 May 2009 23:23:05 -0000
The Shark-Free Marina Initiative has a singular purpose, to reduce worldwide shark mortality. Today the not-for-profit company launches its strategy which intends to prevent the deaths of millions of vulnerable and endangered species of shark. The initiative aims to win over the fishing community by working with game fishing societies, tackle manufacturers, competition sponsors and [...]
Indonesia protects blue whale hotspot and largest area inside “Coral Triangle”
Joni Sat, 23 May 2009 20:06:25 -0000
Great news from MarineBio’s Director of Marine Mammals, Erich Hoyt: The Indonesian Marine Affairs and Fisheries Minister Freddy Numberi has announced the designation of the Savu Sea National Marine Park — a blue whale hotspot that becomes the 15th largest MPA in the world. The announcement came at the World Ocean Conference in Manado, Indonesia, in [...]

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