Life
is all around you, from the tiniest microbes in your gut and the insects
crawling in your garden, to the largest organisms on Earth – the baleen whales.
Biodiversity refers to all life on Earth. “Bio” means life and “diversity”
means variety.
No
one is quite sure how many species we have on Earth. So far 1.7 million species have been identified but the total
number is thought to be somewhere between 5 to 100 million! There is so much life yet to be
discovered.
The
ocean in particular is very rich biologically and there is good reason for
that. Evolution in marine environments has had a 2.7 billion year head start on
terrestrial environments. There are about 40 phyla (major groups of organisms) in the ocean
and at least 15 of these groups are found only in the ocean. Compared to
terrestrial areas though, little investigation has gone into the ocean.
As technology changes, so does our understanding of
the diversity of life in the ocean. High powered microscopes allow glimpses
into the world of microorganisms. Underwater cameras and vehicles reach down
into the deep abysses, to further examine what we can’t otherwise see. So far,
we’ve only had a tantalizing peek at what is really exists. Researchers
estimate that the deep ocean floor may be home to 10 million undiscovered
species!
The vast variety of life on Earth - biodiversity - can be broken down into three levels: ecosystem,
species, and genetic diversity.
ECOSYSTEM
DIVERSITY:
Think about all the different ecosystems that you know about –
deserts, coral reefs, rainforests, the deep sea, ponds, mud flats, and
mountains. (Can you think of any more?) Ecosystem diversity is the broadest
level of biological diversity and is determined by the types of plants,
animals, and microorganisms, as well as the physical characteristics (e.g.
substrate, light, nutrients, etc.) and interactions (e.g. predator-prey
relationships), that exist within an ecosystem.
SPECIES DIVERSITY:
A
species is a group of similar organisms (plants, animals or microorganisms)
that differ from all other groups of organisms and are capable of breeding and
producing fertile offspring. Species diversity combines the number of different
species (species richness) with the relative abundance of a species within a
given area.
(click
here for information about the classification of plants and animals)
GENETIC DIVERSITY:
This is
the biodiversity that occurs within a species. Genes are the blueprints for
life that are passed on from generation to generation. Genes make every
individual different from the rest - genetic diversity. In humans, genetic
diversity is visible in hair or eye colour, or in differences in size and
behaviour. It is the reason why you do not look exactly like your brother or
your sister or any other human being.
So
why is biodiversity important?
Biological organisms are an integral part of and
help maintain processes that regulate global climate and cycle essential
elements (such as carbon, nitrogen and water), all of which keep the Earth
livable. Little is known about marine biodiversity, we are only just beginning
to understand the role marine organisms play in these life processes. For
example, an entirely new group of marine organisms, the prochlorophytes, were
just recently discovered. Although these organisms were previously overlooked,
they are now known to account for a significant portion of the primary
production in the ocean. The health of an ecosystem is dependent on each
species, role, however small.
Biodiversity
has become a critical topic as the ever increasing human population has put
tremendous pressure on the world’s ecosystems for natural resources. Biodiversity
issues impinge in subtle ways on all aspects of our lives, from the day to
day choices we make about consumption and transportation, to the more complex
choices made by our society on how to access and use land and the Earth’s
resources. By learning and thinking about these issues, we can start to understand
biodiversity and our planet’s, as well as our own dependence on it. Hopefully
we can work to preserve biodiversity at all levels worldwide.
to marine biodiversity index
What's New! 
check out Canada's "Centre for Marine Biodiversity" web site!