Where are the Caribbean Atolls?

The ring-shaped coral islands called atolls are a defining feature of the South Pacific, put on magnificent display in the recent Disney-Pixar film Moana. Atolls are known for being convenient harbors almost by default, rich habitats for marine life, and the source of the famous stark line between blue-water and green-water regions that surrounds Pacific islands. Atolls are also extraordinarily rare outside of the South Pacific, which is curious, because neither coral nor islands are similarly restricted. Other warm regions should have their own atolls, but they almost always don’t. So the question is…where are the Caribbean atolls?

A ring-shaped island with a shallow lagoon in the interior and deep blue ocean water surrounding. Where visible, the island ring itself is white with greenery.
Atafu Atoll, Tokelau (a dependent territory of New Zealand near Samoa)

It turns out this is a fairly involved question.

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Where are the Caribbean Atolls?

Animal Form and Function 1: Cnidarians and Flatworms

I’m a big fan of this sentiment:

Being a geek is all about being honest about what you enjoy and not being afraid to demonstrate that affection.  It means never having to play it cool about how much you like something.  It’s basically a license to proudly emote on a somewhat childish level rather than behave like a supposed adult.  Being a geek is extremely liberating.  –Simon Pegg


I try to keep Pegg’s axiom in mind when I’m teaching.  Every winter, I teach the laboratory portion of a course in animal diversity, much of which consists of dissections.  Every week during that course, my students dissect one or more specimens from selected animal phyla and observe without cutting preserved specimens of several more.  Each week comes with a theme, such as convergent evolution, divergent evolution, or metamerism, and ideas such as the state of the body cavity pervade the entire course as well.

Every session of that class where the time is available, I spend the last 15 minutes or so showing videos, still images, and articles about the weirder and more wonderful aspects of the animals within that session.  For many students, classes like these are their one and only encounter with creatures like ragworms and tarantulas.  Augmenting the dry and often harried perspective offered by detailed dissection guides and midterm exams with the novelty and wonder of their living forms is one way that I try to keep this course interesting even for (gasp) pre-medical students who don’t necessarily enter the course brimming with enthusiasm about crayfish and sea stars.

Infectious enthusiasm is the best teaching aid there ever was, and I bring it to my classes even if I have to add my own material to an established course.  This is that material.

Continue reading “Animal Form and Function 1: Cnidarians and Flatworms”

Animal Form and Function 1: Cnidarians and Flatworms