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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! 1. 2. 3. 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. 1. 2. 3. 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…