Planet Earth

Is anyone else watching the Planet Earth series on the Discovery Channel? It stated about a month ago.

See more here.

I wasn't sure if I wanted to watch it or not. I saw a few clips from the 11 part mini series, and it shows you that life on earth is not warm and fuzzy. I know this, so I wasn't sure I really needed to be made more aware. I tend to get emotional over animals and their plight. Thus, I chose not to watch. Well, two weeks ago I was flipping around on Sunday night and low and behold, there it was. I sat and watched for a few minutes thinking I'd change the channel as soon as all the death and gore started. It was the episode I reallllly didn't want to see....the polar bears. I have intentionally not watched the movie "An Inconvenient Truth" because everyone talks about how sad the polar bear segment is. Now I can watch the movie because I ended up watching the whole show and saw the sad polar bear story. I've also continued to watch the series. It's sad, but it also has a lot of parts that are not. It's not a total downer to watch it. So watch it next Sunday...8pm.

But I am digressing from what I was going to post about. This past Sunday it was all about sealife. The ocean scares the crap out of me...no wait, the things in the ocean scare the crap out of me, so I was a little uneasy the whole time I was watching. But it turned out to be okay. And while I was watching, I learned something I have always wondered about....always been curious about. Sand dollars....they were once a kind of sea urchin. They are talking about this deadly octopus that scours the bottom of the ocean eating sand dollars. They showed it suck up this flat spiney sand dollar, liquefy all but it's skeleton, and a monemt later the octopus spits out the skeleton and moves onto the next one. So the pretty white sand dollars we find on the shore are actually skeletons of dead sea urchins. And those things that rattle on the inside of a sand dollars....teeth or something. Makes them a little less charming now. I guess I should have known it was a sea urchin kind of thing. Makes sense now that I know. Just kinda weird.

Here is more information from Wikipedia:

Sand dollars are in the Echinoid (Echinoderms) class of marine animals. When they are living, they are covered with a suit of moveable spines that encompass the entire shell. Like its close relative the sea urchin, the sand dollar has five sets of pores arranged in a petal pattern. The pores are used to move sea water into its internal water-vascular system, which allows for movement by the creature.

Sand dollars live beyond mean low water on top of or just beneath the surface of sandy or muddy areas. The spines on the somewhat flattened underside of the animal allow it to burrow or to slowly creep through the sand. Fine, hair-like cilia cover the tiny spines. Tubefeet or podia that line the food grooves, move food to the mouth opening which is in the center of the star shaped grooves on the underside of the animal called the oral surface. The anus is also located on the bottom, near the posterior edge. Its food consists of plankton and organic particles that end up in the sandy bottom.

On the ocean bottom, sand dollars are frequently found together. This is due in part to their preference of soft bottom areas, which are convenient for their reproduction. The sexes are separate and, as with most echinoids, gametes are released into the water column. The free-swimming larvae metamorphose through several stages before the skeleton or test begins to form, and they become bottom dwellers.

The name "sand dollar" is a reference to their round flat shape, which is similar to a large coin.

The term "sand dollar" can also refer to the test left when a sand dollar dies. By the time the test washes up on the beach, it is usually missing its velvety covering of minute spines and has a somewhat bleached appearance due to its exposure to the sun.