Biological Classification
Why Classify? To study the diversity of life, biologists use classification systems to group organisms according to evolutionary relationships (common ancestry). This makes the diversity of life easier to study. Taxonomy – discipline to group organisms hierarchically and assign each organism a universally accepted name.
Carl Linneaus The modern system of taxonomy used today was created by Carl Linnaeus in the 1700s. It included a naming system called binomial nomenclature which literally means two-name naming system.
Binomial Nomenclature (scientific names) Generic namespecific name Group of closely related species Group of organisms maintained by biological mechanisms that result in their breeding mostly with their type (interbreeding) Rules: 1.One binomial name for each species 2.Capitilzed Generic, lowercase specific. Ex: Homo sapiens, Tyrannosaurus rex 3. Constructed according to rules of Latin or Greek grammar 4. Discoverer of species gets naming rights 5. Typed in italics, underlined when written
Specific names can’t stand alone! Centropyge bicolor Baeolophus bicolor Boletus bicolor Labio bicolor Ecsenius bicolor Loxocemus bicolor Phyllobates bicolor Euphorbia bicolor Gila bicolor Epalzeorhynchus bicolor Rhamnusium bicolor Chilobrachys bicolor Calendula bicolor Lespedeza bicolor Flabellina bicolor Eucomis bicolor Androctonus bicolor Saguinus bicolor
Specific names can’t stand alone!
Match the binomial name to the bear A.Brown (Grizzly) Bear B.American Black Bear C.Giant Panda D.Polar Bear ___ Ursus arctos ___ Ursus maritimus ___ Ursus americanus ___ Ailuropoda melanoleuca
Convergent Evolution Convergent evolution produces analogies, which are NOT useful in classification
Divergent Evolution Divergent evolution produces homologies (from a common ancestor) which are useful in classification
DNA Comparisons Similar DNA sequences are molecular homologies which are useful in classification
Embryo Comparisons Embryos reveal homologies which are useful in classification adult tunicate
What’s a Blue Tang? Acanthurus coeruleus Atlantic Paracanthurus hepatus Indo-Pacific
Paracanthurus hepatus is commonly called blue tang regal tang hippo tang palette surgeon fish flagtail surgeon fish blue surgeon fish other languages?
Biological Classification is Hierarchical K ing P hilip C ut O pen F ive G reen S nakes Which taxonomic group has the most diversity? The least? Which taxonomic group has organisms that are most closely related? Least?
Taxonomic Classification Blue TangYellow Tang Kingdom Animalia Phylum Chordata Class Actinopterygii Order Perciformes Family Acanthuridae Genus ParacanthurusZebrasoma Species P. hepatusZ. flavescens
Taxonomic Classification Blue TangPercula Clownfish Kingdom Animalia Phylum Chordata Class Actinopterygii Order Perciformes Family AcanthuridaePomacentridae Genus ParacanthurusAmphiprion Species P. hepatusA. percula
Taxonomic Classification Blue TangGreat White Shark Kingdom Animalia Phylum Chordata Class ActinopterygiiChondrichthyes Order PerciformesLamniformes Family AcanthuridaeLamnidae Genus ParacanthurusCarcharodon Species P. hepatusC. carcharias
Taxonomic Classification Blue TangHuman Kingdom Animalia Phylum Chordata Class ActinopterygiiMammalia Order PerciformesPrimate Family AcanthuridaeHominidae Genus ParacanthurusHomo Species P. hepatusH. sapiens
CaimanParrotT. rex Animalia Chordata ReptiliaAvesReptilia