Sea Anemones: Who Said the Spineless Can’t be Interesting?
Sea anemones are one of the most exotic and fascinating creatures that inhabit our world’s oceans. Sadly they’re also one of the most exploited, as the current estimated value for the import of marine fish and invertebrates is at US $200-300 million. So what exactly makes this spineless creature so amazing?
The sea anemone is a water dwelling, usually predatory animal named after the terrestrial flower anemone. It’s closely related to jellyfish, and more than a 1,000 species are found throughout the world’s oceans at various depths. They can be as small as an inch or as large as six feet, the Merten’s carpet sea anemone being the largest with a diameter of over 1 meter.
The sea anemone is basically a small sac, and it attaches itself to a surface with the help of an adhesive foot, called a basal disc. It has a cylindrical body which ends in an oral disc, its mouth at the center of this disc, surrounded by tentacles armed with stinging cells. The cells have evolved in such a way that they attach themselves to the organisms that trigger them, and inject a dose of poison into the flesh of the predator or prey. This is also the reason for the characteristic “stickiness” of a sea anemone.
The sea anemone poison is a mix of toxins, including neurotoxins, which paralyze prey, which are then moved to the mouth by the tentacles for digestion. The toxins are also known to act as repellants against other predators when they’re released in water. Clownfish, who share a symbiotic relationship with sea anemones, are not affected by their host’s sting.
The sea anemones are anatomically simple creatures. They have a primitive nervous system, which without centralization, coordinates the processes involved in digestion, as well as biochemical and other physical responses to stimuli. They can have anywhere between as few as ten to as many as hundreds of tentacles.
Although some species are predatory, some anemones form symbiotic relationships with green algae by providing the algae with sufficient exposure to sunlight and protection from herbivores, sea anemones receive oxygen and sugar, the bi-products of the algae’s photosynthesis.
The other more famous symbiotic alliance is with the clown fish, which are covered by a mucus layer that makes them immune to the sea anemone’s stings. The sea anemone protects the clownfish from predators, who in return on undigested and decaying matter that could potentially harm the sea anemone, also the fecal matter produced by the clownfish provides nutrition to the sea anemone. Clownfish are the only species of fish that can avoid the potent sea anemone’s stings.
Most sea anemones spend most of their lives in one place, though some have the ability to move at a pace of about three to four inches an hour. Sometimes they hitch rides on hermit crabs or decorator crabs. The crabs are protected from predators, and the sea anemones get nutrition from bits of uneaten food provided by the crabs.
The sea anemones have long life spans with slow growth rates; also their reproduction rates are considerably lower than those of the resident fish. These are the primary reasons for the exploitation of sea anemones, according to estimates the US amounts to 80% of the $200-300 million industry imports.
The sea anemones play a critical role in the ocean’s biosphere; their overexploitation directly affects the resident fish, crab, shrimp and algae population. The most severely hit organisms are the anemonefish, which primarily depend on the sea anemones for their nutrition and protection.
Did you know that we homosapiens, the most intelligent species in the solar system (for now), share 80% of our DNA with these wondrous creatures. It shows how the complexity in the genome is not connected in any simple way to complexity of the organism.
The research helped us trace our evolutionary roots even further back in time to a pre-animal era. The sea anemones are exceptional relics of our planet’s primitive creatures, and are shockingly more closely related to us than we would have ever thought.
For the natureophille,
Starfish: Stunning Sentinels of the Seas
More popular for their appearance rather than their anatomy, with colors that’ll mesmerize even the greyest of our species, the starfish are undoubtedly some of the most stunning creatures found in the earth’s oceans.
Stick Insects: Mimicking Takes a Whole New Meaning!
Stick insects have some of nature’s most remarkable camouflage skills; unless you have an eye of a hawk, they’re almost impossible to differentiate from their natural surroundings.
Twisted Nature: Craziest Animal Hybrids
Did you know that animals called camas, ligers, tigons or zorses exist? They do! They’ve been around for as long as man has, though they’re extremely rare.
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31 Responses to “Sea Anemones: Who Said the Spineless Can’t be Interesting?”
On February 15, 2009 at 2:46 am
Interesting piece Amit. Great photos. Didnt know we shared so much DNA with these creatures! Weird.
RJ
On February 15, 2009 at 4:14 am
What a wonderful article and so beautifully illustrated. Just what I needed to start my relaxing Sunday morning here in the UK!!
On February 15, 2009 at 6:00 am
Amazing images. I like the greenish-white one… looks likes a bath brush.
-thestickman
On February 15, 2009 at 7:16 am
good information.
On February 15, 2009 at 9:01 am
Amazing pictures, and story line. The information is interesting, things that I did not know about under water life.
On February 15, 2009 at 11:40 am
Wonderful sea matter,I have learned alot.
On February 15, 2009 at 1:03 pm
We are so close to all Creation and DNA is the porve of that, great article.
On February 15, 2009 at 8:46 pm
Very nice article. I see you put a lot into this piece. Well done.
On February 16, 2009 at 12:55 am
Interesting article; great pics.
Inna
On February 16, 2009 at 12:52 pm
A really good article Amit. The colourful pictures you have used, to illustrate, are stunning. Avery infomative read as well.
On February 16, 2009 at 3:34 pm
I liked your article just because I love sea creatures in general.
On February 16, 2009 at 8:35 pm
Great article. Great pictures.
On February 16, 2009 at 11:20 pm
Great pictures. I like it.
On February 17, 2009 at 1:15 am
Those images are fantastic.
I LOVE the title you gave the post!
On February 17, 2009 at 9:07 am
Terrific Pictures Amit.. Very Interesting..
On February 17, 2009 at 1:26 pm
Excellent article, thank you for sharing. I did not know clownfish were the only fish who could coexist in this way.
On February 17, 2009 at 2:10 pm
I like your article and hope that we can be friends!
On February 18, 2009 at 9:21 am
These pictures are fantastic! Thank you so much. Jax
On February 18, 2009 at 9:27 am
Interesting article. The pictures draw you in, before you start reading the article.
On February 18, 2009 at 12:29 pm
Great article. Sea anemones are amazing creatures in every sea. I love going under the water to see those wonders. I have by the way a few articles about diving.
On February 19, 2009 at 3:45 am
Cool photography and interesting article. Well done!
God Bless,
Nelson Doyle
On February 19, 2009 at 4:26 pm
Well written and interesting article, with gorgeous photos, Amit! I was inclined to blog it, but it looks as though RJ has already beat me to it.
On February 22, 2009 at 11:59 am
Wow!! That was a great article with awesome pictures and information. Thanks for posting it!!
On February 23, 2009 at 8:12 am
Awesome article and photography!
On March 1, 2009 at 3:26 pm
Fantastic photos and very interesting article to read about these sea anemones. Thanks for sharing.
On March 15, 2009 at 11:26 pm
The pix look gr8 man!
On April 5, 2009 at 5:08 am
Very interesting, awesome title, lovely images
On April 21, 2009 at 4:45 pm
wow, and wow for the amazing pics too.
On April 22, 2009 at 7:55 pm
I’m a huge fan of beautiful and intricate sea creatures. Thanks for writing about them. I am learning so much from articles like this.
My best to you,
Momma Tells
On April 23, 2009 at 3:12 pm
I think anemones are the coolest animals EVER! And I am doing a HUGE project on them! giggle giggle!!!!!!!!!!!!
On April 23, 2009 at 3:15 pm
luv tha pics and rlly colorful
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