1. History of Biological Taxonomy BIOL447/647 21 January 2016

2. William Sharp MacLeay (1792-1865)  1821: circles-within- circles taxonomy  Always five circles  “Osculant” types joined each circle to two adjacent circles  Types of circle correspond, from one set to next

3. Animalia’s five circles  Vertebrata—(vertebrates)—"typical"—"most perfect"  Annulosa—(arthropods)—"subtypical"—well- armed for conflict, noxious, destructive, "evil"  Radiata—(jellyfishes)—"natatorial"—highly aquatic  Acrita—(corals, hydras)—"suctorial"—"low, imperfect"; feed by "suction"  Mollusca—(mollusks)—"rasorial"—domesticated and useful (i.e., as shellfish)

4. Vertebrata's five circles Typical—Mammalia Subtypical—Reptilia Natatorial—Pisces Suctorial—Amphibia Rasorial—Aves

5. HANDOUT—O’Hara 1986

6. More MacLeayian taxonomy  Other subtypical groups: Ferae among Mammalia; shrike family among Raptores; Ophidia among Reptilia  Other natatorial groups: Cetacea among Mammalia; Cephalopoda among Mollusca  Other suctorial groups: Testudines among Reptilia; Coleoptera among Insecta; armadillos and pangolins among Mammalia  Other rasorial groups: ungulates among Mammalia; Canidae among Ferae; Hymenoptera among Insecta

7. MacLeay’s Influence  Enthusiastically supported in Chambers' Vestiges of the Natural History of Creation (1845)  Intrigued Darwin for a time, during 20 years he had Origin on a back burner

8. Charles Robert Darwin (1809-1882)  Origin of Species (1859) included predictions about phylogeny reconstruction: "Our classifications will come to be, as far as they can be so made, genealogies; and will then truly give what may be called the plan of creation. The rules for classifying will no doubt become simpler when we have a definite object in view."

9. The Only Illustration in Origin of Species (1859) Sketch in private notebook, 1837

10. Darwin’s Barnacle Work  Darwin's only work on taxonomy, in 4 volumes (1846-1854) Jos. Hooker had told him Origin would be better received if he had done taxonomic work  No reference to evolution, but clearly phylogenetic

11. Ernst Haeckel (1834-1919)  Professor at Jena  Coined phylogeny, phylum, and ecology  Developed visual phylogenetic tree  Biogenetic law: “Ontogeny recapitulates phylogeny."

12. Three Schools of Thought (Late 1800s Into Early 1900s)  Differing views on … (a) how evolution proceeds (b) whether characteristics evolve only once (homology), or numerous times, independently (homoplasy) thus (c) whether phylogenetic reconstruction can be accurate  Darwinism  Neo-Lamarckism  Orthogenesis

13. Darwinism  Natural selection = primary agent of change  Adaptations rarely evolve more than once independently  Phylogeny reconstruction should be possible Proponents: Darwin Thomas H. Huxley (1825-1895) E. Ray Lankester (1847-1929)

14. Neo-Lamarckism  Adaptations acquired by an organism are passed to offspring J.B. Lamarck's Philosophie Zoologique (1809)  Multiple origins from similar environmental pressures ("convergence")  Phylogeny difficult to reconstruct  Finally discredited by rise of genetics in early 1900s  Proponents: Haeckel Frederick Wood Jones (1879-1954) Edward Drinker Cope (1840-1897)

15. Orthogenesis  Theistic view Internally-directed evolution a sort of “plan of God” Various groups have same internal plan (“parallelism”) Major taxa had a pre-directed ontogeny, unlinking organism and environment, ending in extinction  Much room for multiple origins of characteristics  Would greatly obfuscate phylogeny reconstruction  Proponents: St. George Jackson Mivart (1827-1900) Henry Fairfield Osborn (1857-1935)

16. International Code of Zoological Nomenclature  Late 1800s: countries adopted differing codes of nomenclature  1901: 5th International Zoological Congress, resulted in the first International Code of Zoological Nomenclature (issued 1905)  Revised periodically since then Most recently in January 2000, with revisions covering such items as web-based publications  International Commission on Zoological Nomenclature (ICZN) issues opinions

17. Three Competing Schools of Thought (Latter Half of the 20th Century)  Evolutionary Taxonomy  Phenetics  Cladistics

18. Evolutionary Taxonomy  Major proponent: Harvard's Ernst Mayr (1904-2005) Systematics and the Origin of Species (1942) Principles of Systematic Zoology (1969)  “Old school”  Classifies based both on phylogenetic relationships, and degree of differentiation within parts of an evolutionary tree

19. Phenetics  Classification based on overall similarity, reasoning that similarities result from common ancestry  Strong early reliance on computer analyses Numerical Taxonomy (1963) by R.R. Sokal and P.H.A. Sneath

20. Cladistics  Classification solely on shared derived characters (=synapomorphies) Ignore ancestral features (=plesiomorphies)  All members of taxon are more closely related to other members of that taxon than to members of any other taxon of equal rank  German entomologist Willi Hennig (1913- 1976): the “father” of cladistics Grundzűge einer Theorie der phylogenetischen Systematik (1950) English synopsis in a review article (1965) and English translation, Phylogenetic Systematics (1966)

21. And the Winner is… Willi Hennig

22. Schuh and Brower Table 1.1 p. 12

23. The Rise of Molecular Methods  Protein electrophoresis comparisons began in mid 1960s, popular by 1970s  Restriction enzymes then just beginning to be used on DNA, with electrophoretic separation  DNA sequencing invented in 1977  PCR invented in 1987  Minisatellite DNA studies started 1987

24. Readings for Next Time  Schuh & Brower:173-188; 201-208  Winston:129-188; 407-432  Additional:None