Transcript Slide 1
David Vaughan 2651582,
[email protected]
Available at http://planet.uwc.ac.za/nisl/Eco_people/Presentations/
D. Vaughan Two Oceans Aquarium
Becwethan*-biodiversity
What exactly is Biodiversity?
Life on Earth is extremely diverse, ranging from the simplest
unicellular forms to highly specialised creatures.
BIODIVERSITY encompasses the following:
- Genetic variation within species
- Interrelationships between species
- Geographical dispersion of species
- The links between local and global ecosystems
- How the above change over time
In short, BIODIVERSITY is the singular conceptual description of all
variety of life on Earth functioning as a dynamic.
BIODIVERSITY has to be measured for us to appreciate its diversity
and importance.
How is this done, and who started the classification of everything?
D. Vaughan Two Oceans Aquarium
In the beginning…nobody had a clue!
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Storing information about past and present biodiversity was
introduced as an idea by Aristotle in Greece from about 350 BC.
Aristotle was first to attempt classification of animals and plants.
Initially plants and animals were separated from each other.
Animals were then separated into 3 groups:
Animals that lived on land,
Animals that lived in the sea,
Animals that lived in the air.
This first classification was not accurate.
D.MNH
Vaughan
Oceans
Aquarium
2001 Two
Annual
report
(no.2)
Theophratus introduced the first classification using structural
similarities.
The birth of classification and documentation.
Theophratus’ classification system is the hierarchical system most
similar to that of today.
Recognised hierarchical classifications typically include:
Empirical evidence from observation
KINGDOMwas used to justify classification.
Descriptive morphology (taxonomy) was invented.
PHYLUMof classification systems and the
For the first time in history, because
first scientific writing, literary text could now officially document taxa!
CLASS over 1000 species in early text.
Aristotle and Theophratus mentioned
Aristotle produced a key to unlock information about his classification
ORDER
system.
With this key, you can deduce the specific features used by Aristotle
FAMILY
to classify animals…
GENUS
SPECIES
http://www.solaster-mb.org/mb/images/dyrynda-matrix-comb-1-wl.JPG
Keys…
Aristotle’s key:
Animals
Red blood
No red blood
Mammals
Soft bodies
Hard bodies
Lizards
Birds
Fish
Insects
Shell
No shell
Shellfish
Jellyfish
Aristotle’s key is both a branched key, and a dichotomous key.
Dichotomous keys separate each classified group into TWO parts.
Scientific classifications belong to the science of TAXONOMY, or the
science of BIOLOGICAL SYSTEMATICS.
The science of taxonomy.
Carolus Linnaeus is known as the father of modern taxonomy.
Established conventional naming of
living organisms, known commonly
as the convention for
Binomial nomenclature.
Binomial from Latin “Binomium”
meaning “two-portion.”
Formal method of naming species.
Genus, species eg. Homo sapiens.
Always printed in italics, or underlined
in text.
Genus names always begin with a
CAPITAL letter.
Taxonomy is the describing, identifying
naming and classifying of organisms.
http://en.wikipedia.org/w/index.php?title=Carolus_Linnaeus&oldid=119578483
The science of taxonomy continued.
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The standardisation of nomenclature used for species provides a
more inclusive environment through which information about
biodiversity can be shared, discussed, and peer-reviewed.
Advantages of the binomial nomenclature system include:
Every species can be identified without ambiguity using just two
universally accepted words.
Universally accepted names can be understood in many different
languages since the spelling remains the same.
Although names do change, scientific names remain relatively stable.
The invention of the microscope and the use of similarities in
morphology fuelled the development of taxonomy.
All photomicrographs © D. Vaughan Two Oceans Aquarium
The science of biological systematics.
‘Species and groups of species gradually disappear, one after another,
first from one spot, then from another, and finally from the world.’
– Charles Darwin (1859) “On The Origin of Species.”
What is biological systematics?
The study of the diversity of life, past and present.
The study of the relationships between all living things.
Only systematics deals with these relationships through time.
This requires knowledge of the fossil record.
Systematics uses taxonomy as a tool to understand
relationships between animals.
Scientists specialising in systematics must be able
to use existing classification systems.
The science of biological systematics.
Phenetic systematics clarifies biodiversity through time by making
use of the morphology and physiology of organisms.
Phylogenetic systematics (Cladistics) uses important evolutionary
characteristics of organisms and their relationship through time.
Modern systematics commonly makes use of molecular genetics (e.g.
DNA), and computer software to study organisms.
Systematics is the foundation for all studies on all organisms.
Systematics shows how many organisms are related.
Through systematics, an attempt is made to understand the Earth’s
biodiversity.
This assists with the understanding of conservation of species and
can also be used to specify the minimum amount of genetic diversity
required to preserve endangered taxa.
Cladistics.
Cladistics is the classification philosophy arranging organisms by
their branching in what’s called an evolutionary tree.
Morphological similarities are not used.
Cladograms are the visual representation of these evolutionary trees:
Beetles
Wasps, Ants, Bees
Moths, Butterflies
Flies
A cladogram such as the one above, is a hypothesised relationship.
The taxa on either side of a split in the tree are sister taxa or sister
groups.
The plight of systematics.
Biological exploration has huge intellectual and scientific rewards,
however…
Internationally, the amount of trained taxonomists is declining, as is
the financial support for the important work which they produce.
The extinction of species, regardless of the rates of extinction,
threatens us with biological ignorance.
Where do we begin to look for new medicines, fibres, molecules or
even genes that we can use for the future benefit of our own species
without the support of systematic sciences?
Taxonomic inventories need to be compiled using surveys of
biodiversity.
Sufficient funds must be supplied for the maintenance and building of
additional museums, herbaria and public aquaria, the primary
repositories for what is known about biodiversity.
Global comprehensive collections of animals are supportive of
efficient taxonomy.
Reference collections provide
information about local species
diversity both past and present.
Databases on various taxa are
maintained at the research site
where the expertise, library resource
and collections exist.
Data are backed up with voucher
specimens.
Voucher specimens provide a biological reference to which
questionable records can be “truthed.”
http://www.royalsaskmuseum.ca/research/images/saskbugs.jpg
Reference collections.
Reference collections.
“Specimen” means the whole animal or part thereof.
Reference specimens are usually differentiated into the following:
HOLOTYPE: A single type specimen from which the original
taxonomic description and the name of a new species is based.
PARATYPE: Type specimens from the original collection of specimens
from which the original taxonomic description and name of a new
species is based.
VOUCHER SPECIMEN: Any specimen, usually dead, but not always,
that serves as a basis of study and is retained as a reference.
Holotypes are seldom allowed to leave the museum where they were
deposited and represent significant value to biodiversity.
Paratypes are more often allowed to leave the museum for verification
and assistance with scientific work.
Reference collections.
The National Museum of Natural History in the USA houses one of the
most important mammal collections in the world.
http://newsdesk.si.edu/photos/buildings_general.htm
580 000 voucher specimens, 3500 holotype specimens.
The taxonomic and geographic reflections within this collection are
world-wide.
All museum collections are maintained for posterity, and as
irreplaceable resources.
Importance of museum collections.
Museum collections include scientific specimens that are relevant to
the museums mandate. Many reference collections are kept in
museums.
Museum collections are important resources, valuable for the
information they provide.
All museum records associated with museum collections are usually
managed as museum property.
Museums educate the public with exhibits.
Exhibits give a visual reference to why systematics is important.
Exhibits can be dead or living.
Herbaria are museums of dried plant collections.
Vivaria are enclosures for keeping or raising organisms for research
or observation.
Gene banks (Genbank) are nucleotide sequence databases and DNA
storage (cryogenic) facilities.
Herbaria.
http://www.flmnh.ufl.edu/herbarium/herbariaandspecimens.htm
The first botanist to invent a herbarium was Luca Ghini in 1551.
Herbaria often make use of dried plants
mounted on special paper, or preserved
in alcohol (this also includes fungi).
Herbaria are essentially important to the
study of plant taxonomy.
Herbaria are useful sources of plant DNA.
Herbaria are also useful in studying the
geographic distributions of plants.
Herbaria of toxic plants provides us with
information on what to avoid, and what
medicinal properties certain plants have.
The oldest herbarium in South Africa is
that of the South African Museum (SAM) which houses some 750 000
specimens from the Winter rainfall regions of South Africa.
Vivaria
Vivaria often recreate a portion of the ecosystem for a particular
species in captivity.
Vivaria therefore maintain live exhibits.
Public aquaria and zoological gardens are large “vivaria” specialising
in exhibits of animals of many different varieties.
All images © D. Vaughan Two Oceans Aquarium
Public aquaria and zoological gardens educate and provide a visual
experience of a world not often seen by the general public.
Public aquaria.
A public aquarium is the aquatic counterpart of a zoo.
Today, most public aquaria have a research component which lends
itself to the conservation of marine species.
The Two Oceans Aquarium in Cape Town supports the Save Our Sea
Foundation, and works closely with the Sustainable Sea Food
Initiative.
A public aquarium’s mandate is one of conservation as well as
education.
Educating the public about the limited natural resources, fragile
interconnectedness of species and the rates of habitat destruction,
provides awareness.
Education overcomes ignorance
Public aquaria have a responsibility towards the exhibit animals under
their custodianship.
Picture credits cited in the notes.
Organisations.
Most zoos and public aquaria are affiliated with WAZA (World
Association of Zoos and Aquariums): http://www.waza.org
WAZA is the umbrella organisation for leading zoos and aquaria and
includes specialist advisory staff including veterinarians, ‘united for
conservation.’
WAZA’s vision is ‘to be recognised as a trusted and leading partner in
the conservation of biodiversity.’
PAAZAB (The African Association of Zoos and Aquaria):
http://www.paazab.com ‘sees one of the primary functions of zoos and
aquariums as healing the relationship between man, animal and their
mutual environment.’
PAAZAB represents the interest of bona fide zoos and aquaria on the
African continent.
Gene banks (genetic information preservation)
The National Centre for Biotechnology Information (NCBI) produces
the open access nucleotide sequence database called GENBANK.
GENBANK is an annotated collection of all the
publicly available nucleotide sequences. This
includes their protein translations.
Over 100 000 distinct organism sequences have
been received.
GENBANK was one of the first bioinformatics community projects on
the Internet.
The GENBANK database is designed to provide the scientific
community with up-to-date DNA sequence information.
Storing information about DNA provides information for future
conservation initiatives and information on genetic diversity of
species and populations.
Conclusion
Much effort has been placed on the preservation and understanding of
biodiversity over the centuries.
With the development of classification systems, storing information in
literary text, to today’s data banks and computer systems, a better
understanding of biodiversity is being created.
A good understanding of biodiversity allows us to see our impacts on
biodiversity over time.
Biodiversity exploration assists with our own development as a
species.
Education of the public through museums, herbaria and vivaria,
improves biodiversity awareness and combats blind ignorance.
Within the current mass-extinction event, we document our loss in the
hope that future generations may one day prevent the possibility of
our own extinction…