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Underwater Naturaliast Course

Who Are You Calling an Invertebrate?

Posted by | Articles, The Incredible Showcase, Underwater Naturaliast Course | No Comments

Ernst Haeckel (1834-1919) juggled many professional hats during his life – he was a professor, biologist, philosopher, physician, and in the middle all that, he found the time to be a phenomenal artist as well. He is known for his enormous contribution to science, through the several new species he discovered, scientific concepts he theorized and biological terms he coined. He is also admired across various disciplines for his exquisite and influential collection of illustrations known as the ‘Kunstformen der Natur’ or ‘Artforms in Nature’ (sketched and painted between 1899 -1904).

If you are looking at any of these plates and admiring them for their abstract beauty or commending Ernst Haeckel for his marvellous attempt at science-fiction, take a look again. These are all real marine animals. They actually exist in these very shapes, patterns and forms. Ernst Haeckel observed and appreciated that in these underwater beauties; several decades before the advent of recreational SCUBA diving.

What do all these animals have in common? On careful observation you will notice that, yes they are all stunningly beautiful, there is inherent symmetry, but also, they are all types of ‘invertebrates’. They are all animals that lack a vertebral column or a backbone/spine inside their bodies.

Speaking of invertebrates, I never did understand the figurative use of this term in our society. To call someone a ‘spineless’, ‘invertebrate’ is to describe them as weak, cowardly, inadequate or ineffective. How did this association come to be?

Over 97% of animals on this planet are spineless, especially in the ocean. Some of the most venomous (box jellyfish), strongest (mantis shrimp), smartest (octopus), fastest reflexes (mantis shrimp again!), largest (giant squid), cutest (alright, this one is heavily subjectiveJ) are some form of marine invertebrate or the other.

A barrel sponge (Xestospongia testudinaria) can dwarf you despite your tank and fins
Vandit Kalia @vanditkalia

When reading about evolution and biology today we learn that, more and more, science doesn’t consider evolution to be progressive. Meaning to say that through the course of geological time, being older or having appeared first is no longer considered ‘primitive’ and being more newly evolved doesn’t make you necessarily ‘advanced’. Scientists now prefer to use terms such as ‘ancestral’ and ‘recent’ instead, with much less value judgement. Take sponges for example. Sponges consist of hollow cavities held together by protein fibres and they have numerous different types of cells, to filter food from water that is brought in and sent out. Sponges constitute some of the oldest animals to have ever lived (fossils as old as 640 million years old), and they still exist, all of 9,000 species of them.

A wise old coral colony
Gunnhild Sørås  
@gunnigullet    Vikas Nairi  @vikasnairi

Backbone-free animals are everywhere, and some of them literally shape our world. During the journey of a single dive in a shallow reef, we are immersing ourselves into a world whose multi-dimensional foundation, was built over millions of years, by the remarkably and astonishingly, spineless coral. Stony coral get a majority of their energy from their in-house photosynthetic symbionts and use it to put down calcium carbonate skeletons, layer by layer, that are strong enough to last years, centuries, and millennia. Corals live and lay the foundation of coral reefs, and then everyone else, from feather-duster worms to fish, start to step in to look for ways to build their own lives. An ecosystem is formed.

A closing sea anemone
Chetana Babburjung
 @chutney_babburjung

Through the course of your dive, you will surely find yourself smiling at clownfish in their anemones. Unlike a majority of their coral cousins which live as colonies of polyps, sea anemones are typically singular polyps lined by a whorl of stinging tentacles. Hidden in the centre of the anemone, if clownfish will allow you to see it, is an opening that is its singular window to the outside world- mouth and anus. It happens rarely and very difficult to catch with the naked eye, but sea anemones can move.

A peacock tail anemone shrimp busy on its host anemone
Gunnhild Sørås 
@gunnigullet

Anemones are cheerful hosts that collaborate not just with clownfish, but a variety of crustaceans, especially anemone shrimps and crabs that promise to help the anemone stay clean in return for a home.

Nudibranchs, a cryptic treasure.
Gunnhild Sørås 
@gunnigullet

Some of the more cryptic treasures to look out for on a reef are sea slugs, who are now coming out of the shadow of their celebrity cousins-the octopus. Among the mind-blowing diversity of sea slugs, nudibranchs are unique in that they breathe through gills placed outside their body (hence the name). While they have a versatile diet, some of them love eating fern-like hydroids. Hydroids just like their relatives -coral, anemones and jellies- are laced with stingers. No matter, Aeolid nudibranchs eat them anyway, carefully pocketing the stingers for later use as self-defence. Similarly sap-sucking slugs feed on algae but extract the algal pigments and keep them alive in their bodies for their own personal photosynthetic use. Is that ingenious, or is that ingenious?

Ernst Haeckel was particularly taken by the symmetry he saw in nature. A classic example for us would be- Echinoderms. A group found exclusively in the ocean, echinoderms are the sea stars, feather stars, brittle stars, urchins, cucumbers and several other unbelievable but underappreciated marine invertebrates (and therefore warrant a separate feature altogether).

A mollusc larva dancing in the blue
Vikas Nairi 
@vikasnairi

A typical shallow dive might last forty-five minutes to an hour and we may still not be ready to ascend to the surface, even though the gases in our tanks and bodies might dictate otherwise. But wait, the dive isn’t over yet.  Safety stops are the best time to connect with bizarre but brilliant drifting creatures, as we hover in an endless soup of plankton.

At the end of the day, if Boris Johnson were to ever call me a “supine invertebrate jelly”, I think I might just say, thank you.

Watch this space for our next  showcase on the underwater lives of the Incredibles.

The author, Chetana is a PADI divemaster and resident biologist at DIVEIndia in the Andaman Islands. She is an alumnus of the Masters program at the Wildlife Conservation Society -India program and National Centre for Biological Sciences in Bengaluru. She has been diving and exploring the Andaman Islands since 2013. She is also deeply excited about forests, birds, reptiles and amphibians.

Back to School dive package

Back To School Dive Package: Underwater Naturalist

Posted by | Scuba diving Courses, Underwater Naturaliast Course | No Comments

Introducing the Back to School dive package!

If the ocean were your classroom, would you like to go back to school?

If you have been looking to know more about the marine environment and how life works underwater or if you would like to learn how to identify fish and other reef organisms, this two day package is for you! Learn more about some of the conservation challenges our oceans are facing and help us come up with solutions to protect these magical places.

We also offer this package as an Underwater Naturalist specialty through PADI and SSI open to any diver with at least an Open Water certification.

This program runs over two days and includes short theory classes and discussions along with four open water dives. You can also choose to do a night dive as one of the four dives.

During this course we introduce you to some of the numerous ocean ecosystems (yes, there is more than one!). We take you through how environmental factors shape these coral reefs as well as our experiences when we dive these sites. Reefs are extremely diverse spaces, where survival is based on cut-throat competition but also to an equal measure on cooperation and forging partnerships. Learn about some of these interactions as they unfold like a show around you on every dive! You also get to try your hand at identifying fish and other reef organisms and be a part of REEF LOG, the first diver-led reef monitoring program here in the Andamans!

Image courtesy: Gunnhild

Marilia and Jugal were the first two students on this course package.  Here is what Marilia had to say, Diving became much more interesting after a short Underwater Naturalist course, that basically introduced micro life, which I couldn’t identify before, and explained the relationships between the animals down there.” Jugal feels that understanding more about the underwater environment is rewarding on various levels. Knowledge of fish identification, understanding of interactions between organisms, relation between organisms and their environment are few aspects this course develops, which make every dive more interesting, fun and fulfilling. It also makes you aware of the importance of conservation through individual and collective efforts. Learning through discussions and reading along with practical demonstration (during dives) of everything in live action makes for a beautiful experience while developing a special tool to take away and make use of in all future dives!”

Diving with a naturalist’s perspective can also be fun.

To get more information on the same, please email us.