WEBVTT

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These spider crabs, Macroregonia
macrochira,

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were collected from a depth of 2,900
meters on Pratt Seamount.

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After I remove the crabs from our traps,

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I take them to the lab
so we can take our samples.

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Crabs have an open circulatory system,
which means that their blood

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passed through cavities, called sinuses.

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They are low pressure
compared to the vessels in our own closed

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circulatory system.

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After we take a three milliliter
blood sample, we look for any Craprellid

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amphipods, which are commensal organisms,
that live inside the crab's mouthparts.

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After looking for amphipods,
we take several measurements,

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including carapace (shell)
length and width.

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We also open up the carapace

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and take a gill sample
that will be used for genetic analysis

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to see how closely related
these crabs are to other species,

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such as the tanner and snow crabs.