5.3 Classification of biodiversity

1. 5.3 Classification of biodiversity Essential idea: Species are named and classified using an internationally agreed system. The Swedish botanist Carolus Linnaeus originally invented the binomial system to help him consistently name plants he identified. The system was eventually adopted by other scientists and remains to the accepted naming system for species. Though species may have many common names to avoid confusion scientists always use the scientific/binomial name. By Chris Paine https://bioknowledgy.weebly.com/ http://www.tokresource.org/tok_classes/biobiobio/biomenu/classification/index.htm

2. Understandings

3. Applications and Skills

4. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

5. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

6. 5.3.U1 The binomial system of names for species is universal among biologists and has been agreed and developed at a series of congresses. The 21st International Congress of Zoology (ICZ) http://iszscon2012.haifa.ac.il/ http://www.ibc2017.cn/index.html • Carl Linnaeus orginally published SystemaNaturain 1758 in which he gave binomials for all species known at that time. • The IBC of Vienna in 1905 voted to accept his naming convention. • Since then both the IBC and ICZ have been the bodies that oversee the international efforts to maintain consistent naming conventions and use of taxon. • Periodically the congresses meet to discuss issues affecting classification. http://www.tokresource.org/tok_classes/biobiobio/biomenu/classification/index.htm

7. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

8. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

9. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

10. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

11. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

12. 5.3.U2 When species are discovered they are given scientific names using the binomial system.

13. 5.3.U7 Taxonomists sometimes reclassify groups of species when new evidence shows that a previous taxon contains species that have evolved from different ancestral species. Historically classification systems have been revised repeatedly based on emerging evidence. Previously in the second half of the 20th century all living organisms were classified into five kingdoms. This included prokaryotes being placed in one kingdom and eukaryotes were split-up into the remaining four kingdoms. Recent evidence from genetic studies of ribosomal RNA has shown that "prokaryotes" are far more diverse than anyone had suspected. ribosomal RNA is found in all organisms and evolves slowly so is a good way to track evolution over long time periods. Recent work http://academic.pgcc.edu/~kroberts/Lecture/Chapter%204/04-23_WhittakerTax_L.jpg

14. 5.3.U4 All organisms are classified into three domains. Revisionof the classification system lead to a new level of taxon called domains. The Prokaryotae are now divided into two domains, the Bacteria and the Archaea Bacteria and the Archaea are as different from each other as either is from the Eukaryota, the third domain. No one of these groups is ancestral to the others, and each shares certain features with the others as well as having unique characteristics of its own. http://www.ucmp.berkeley.edu/alllife/threedomains.html

15. 5.3.U4 All organisms are classified into three domains. Features and examples of each domain: n.b. viruses are not classified as living organisms in the same way that eukaryotes, archaeans, and bacteria are. They are however of considerable biological importance. http://en.wikipedia.org/wiki/Three-domain_system

16. 5.3.U3 Taxonomists classify species using a hierarchy of taxa.5.3.U5 The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family, genus and species. Not all domains use the same taxa – the example above is for Eukaryotes

17. 5.3.U5 The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family, genus and species.

18. 5.3.U5 The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family, genus and species.

19. 5.3.A1 Classification of one plant and one animal species from domain to species level. Learn a mnemonic, one animal example and one plant example: Human Meadow Buttercup http://commons.wikimedia.org/wiki/File:Masai_Woman.jpg http://commons.wikimedia.org/wiki/File:Ranunculus_macro.jpg

20. 5.3.A2 Recognition features of bryophyta, filicinophyta, coniferophyta and angiospermophyta. e.g. e.g. e.g. e.g.

21. 5.3.A2 Recognition features of bryophyta, filicinophyta, coniferophyta and angiospermophyta.

22. 5.3.A4 Recognition of features of birds, mammals, amphibians, reptiles and fish. The most familiar animal from the chordata phyla belong the to subphylum vertebrata. Can you match the different classes with the images? Birds (aves) Amphibians (amphibia) Mammals (mammalia) Reptiles (reptilia) Fish (Agnatha, Chondrichthyes, Osteichthyes) n.b. Fish is not a true class it is actually a grouping of three similar classes. http://commons.wikimedia.org/

23. 5.3.A4 Recognition of features of birds, mammals, amphibians, reptiles and fish. The most familiar animal from the chordata phyla belong the to subphylum vertebrata. Can you match the different classes with the images? Amphibians (amphibia) Mammals (mammalia) Reptiles (reptilia) Fish (Agnatha, Chondrichthyes, Osteichthyes) n.b. Fish is not a true class it is actually a grouping of three similar classes. Birds (aves) http://commons.wikimedia.org/

24. 5.3.A4 Recognition of features of birds, mammals, amphibians, reptiles and fish. A summary of key features that can be used to distinguish between the vertebrateclasses

25. 5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda and chordata. What about other phyla? Can you match the names with the images? platylhelmintha cnidaria annelida mollusca porifera chordata arthropoda http://commons.wikimedia.org/

26. 5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda and chordata. Chordata (animals with a backbone) should be easy. Try using the key to help identify the rest of the phyla.

27. 5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda and chordata. Can you match the phyla with the images? cnidaria mollusca platylhelmintha chordata porifera annelida arthropoda http://commons.wikimedia.org/

28. 5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda and chordata. A summary of key features that can be used to distinguish between animal phyla

29. 5.3.S1 Construction of dichotomous keys for use in identifying specimens.

30. 5.3.S1 Construction of dichotomous keys for use in identifying specimens.

31. 5.3.S1 Construction of dichotomous keys for use in identifying specimens.

32. 5.3.U6 In a natural classification, the genus and accompanying higher taxa consist of all the species that have evolved from one common ancestral species. Natural classification groups together species that share a common ancestor from which they evolved. This is called the Darwinian principle of common descent It is expected that members of a group share important attributes or 'homologous’ traits that are inherited from common ancestors. For example Lions share more traits with Jaguars than with Clouded Leopards. Grouping together birds, bats and bees because they fly would be an artificial classification as they do not share a common ancestor and evolved the ability to fly independently. . Plants and fungi were once classified together because they both possessed shared characteristics such as cell walls. It is now known that this is an artificial grouping as their cell walls have a different molecular biology and they evolved separately. Natural classification is not straightforward as convergent evolution can make distantly related organisms appear similar and adaptive radiationcan make similar organisms appear very different from each other.

33. 5.3.U8 Natural classifications help in identification of species and allow the prediction of characteristics shared by species within a group. “New species of legless amphibian discovered in remote Cambodian rainforest” Natural classification is very helpful when dealing with new species: Dichotomous keys can be used to help identify the species. The keys can place a specimen with the most closely related species, genus, family or phyla using natural classification. To what level of classification a specimen can be placed depends on how unique it is. If a new species of Ant is discovered then scientists would predict that the species should possess amongst other characteristics six jointed legs, a head, thorax, abdomen, elbowed antennae, ‘antibiotic’ secretory glands. If the species does not match the expected set of characteristics this brings into question either the classification of the species or of Ants as a family. http://www.abc.net.au/news/2015-01-17/new-species-of-legless-amphibian-found-in-cambodia/6022048

34. Bibliography / Acknowledgments Jason de Nys