Skip main navigation

Introduction to Marine Vertebrates

Marine animals can be found in every major group of vertebrates except one. Dr. Kathy Townsend explains.
In this section, we’ll introduce you to all the major groups of marine vertebrates and what makes them unique. Hi, I’m Dr. Kathy Townsend, and I’m a specialist in marine ecology at the University of the Sunshine Coast in Australia. You may recognise me from such documentaries as Manta Mystery from NatGeo Wild, or perhaps Sir David Attenborough’s BBCs Great Barrier Reef. Now, first of all, what is it that makes a marine vertebrates? What, what actually isn’t marine vertebrate? Well, marine vertebrates are animals that actually possess a backbone, and they live in either salty or brackish water.
And if we’re going to talk about major groups of marine vertebrates, it’s really important that we quickly touch on how scientists classify animals, and the differences between common names and scientific names. So, biologists name animals using a system called taxonomic nomenclature. It’s used to name, define and classify groups of animals. It was the Swedish botanist Carl Linnaeus, who is regarded as the founder of the current system of taxonomy, as he was the one who developed a ranking system known as Linnaean taxonomy for categorising organisms, and the binomial nomenclature for naming organisms. Now, Linnaean taxonomy is still being used today. And it consists of a hierarchical structure of naming. Now, that probably sounds a little bit confusing.
In this example, we’re going to investigate the Linnaean taxonomy of one of the most recognisable marine vertebrates, the Orca, or to some the killer whale. So orcas are in the Kingdom, Animalia, the Phylum Chordata, the Order Cetacea, the Family Delphinidae, and the Genus, Orcinus, and finally, the Species orca. So people often remember this order using an acronym, such things as King Parrots Only Fly Generally South to remind you that it’s Kingdom, Phylum, Order, Family, Genus and Species. And when you refer to a particular species, you always use binomial nomenclature. So binomial means two and nomenclature is just another term of saying naming. And so what this means is that each species has two names, a genus and species name.
And in the case of orcas, it’s Orcinus orca, it’s a little bit like human beings that have two names. So one of them describes the group that they come from, or in this humans case, the family that I come from. So in my case, it’s Townsend, while the other one is unique to them. So in my case, of course, it’s Kathy. Although my mother does insist, it’s Kathy-Ann. So common names are something completely different from scientific names. We often use these in our day to day language, and they can vary dramatically from location to location. For example, the distinctive leopard shark from Australia is called a zebra shark in the USA.
And if scientists didn’t know that, they’d be thinking they were talking about different kinds of species. Did you know that they’re actually marine representatives in every class within the phylum Chordata, except for one? Can you guess which species or which class doesn’t have animals from a marine vertebrates? And can you possibly guess why? did you guess amphibians? If so, you’d be right. That’s the only group of vertebrates that does not have a saltwater representative. And while many coastal species can tolerate brief excursions into seawater, such as Australia’s non endemic species, or invasive species known as the cane toad, they really are more closely linked to freshwater environments.
So now it’s time to introduce you to each of the different classes of marine vertebrates, starting with sharks and rays

In this section you will introduced to marine vertebrates and the scientific naming system known as binomial nomenclature. You will also learn the difference between common names and scientific names, and why they are important.

This article is from the free online

Life Below Water: Conservation, Current Issues, Possible Solutions

Created by
FutureLearn - Learning For Life

Our purpose is to transform access to education.

We offer a diverse selection of courses from leading universities and cultural institutions from around the world. These are delivered one step at a time, and are accessible on mobile, tablet and desktop, so you can fit learning around your life.

We believe learning should be an enjoyable, social experience, so our courses offer the opportunity to discuss what you’re learning with others as you go, helping you make fresh discoveries and form new ideas.
You can unlock new opportunities with unlimited access to hundreds of online short courses for a year by subscribing to our Unlimited package. Build your knowledge with top universities and organisations.

Learn more about how FutureLearn is transforming access to education