Intro For a gentleman should know something of invertebrate zoology, call it culture or what you will, just as he ought to know something about painting and music and the weeds in his garden. Martin Wells, Lower Animals, 1968

Kingdoms of life Eubacteria, Archaea, Fungi, Plantae Protista ~ 18 Phyla Animalia ~ 34 Phyla

Diversity of known groups Kingdom Animalia 1,000,000+ described species Vert’s (~50,000) Invert’s and other Chordates (~ 1 million) Total species? 10-30 million Or 100-200 million

Phyla with most spp. Arthropoda ~ 1.1 million Mollusca ~ 100,000 Protista ~ 80,000

Invert origins Life on earth: after cooling ~ 4.6 billion YA Eukaryotic cells: ~ 2.7 billion YA Shared ancestors of plants + animals: ~ 1.6 billion YA Metazoans: ~ 600 million YA Evidence?

Geological strata Learn major eras, periods, epochs (of Phanerozoic eon) http://www.ucmp.berkeley.edu/help/timeform.html

Cambrian Explosion? Major phyla first appear and diversify Precambrian Cnidaria and Porifera

Cambrian explosion Paleozoic Mollusca, Brachiopoda, Ctenophora, Priapulida, Onychophora, Arthropoda, Phoronida, Annelida, Echinodermata, Chordata, Hemichordata, Tardigrada, Nematoda, Nemertina

Phyla Brachiopoda, Ctenophora, Priapulida

Phyla Onychophora, Phoronida, Arthropoda

Phyla Annelida, Echinodermata, Hemichordates

Phyla Tardigrada, Nemertina, Nematoda Hookworm

Cambrian explosion Mesozoic Entoprocta, Rotifera, Nematomorpha, Platyhelminthes, Gastrotricha, Acanthocephala

Biomes and ecosystems

Marine ecosystems Most of planet is marine Available habitats: Littoral, pelagic, benthic (epifauna, infauna), interstitial

Estuaries, coastal marshlands Salt marsh Estuary

Freshwater Less stable than marine Requires diapause, hibernation, aestivation

Terrestrial Temperature extremes Lower diversity (except arthropods)

Evolution Anagenesis = microevolution causes changes w/in species Macroevolution: Speciation = birth of a species Extinction = death of a species

Microevolution Changes caused by: Random genetic drift, Natural selection, etc. Changes occur that result in organisms that “fit” their environment

Macroevolution Cladogenesis = origins + radiations of species lineages Mass extinctions Rapid speciation and radiation

What causes major species radiations? Flexible architecture of genetic regulation Developmental pathways undergo major changes with few genetic differences Results in changes in body plan Requires flexible architecture of genetic regulation

Classification, systematics, phylogeny Review basic philosophy of systematics

Classification Ordering organisms into groups By taxa: species, genera, families, etc. How are they grouped?

Nomenclature Rules for naming 1. Each kind of organism has only one correct name 2. No 2 kinds of organism have the same name.

Binomial nomenclature Linnaeus’ system Binomial = Genus + species

ICZN International Code of Zoological Nomenclature: 1758 Principles: Scientific names are Latin, valid name based on first usage, names must be based on type specimens

ICZN in practice Author who first describes species has name following species name Wheel bug, Arilus cristatus (Linnaeus) In parentheses = in different genus than originally placed

Systematics = taxonomy + phylogenetics Study of kinds and diversity of life on Earth, and of relationships between them

Alpha taxonomy Naming species: Describing undescribed organisms Uniting multiple descriptions of same organism

Science of systematics Classical science based on morphology Currently use embryology, physiology, immunology, behavior, biochemistry, molecular genetics, morphology Growing science

Basic terms Monophyletic group = includes all descendants Paraphyletic group = does not include all descendants Polyphyletic group = some arose from different ancestors

Characters Attributes of organisms used in comparisons Homology = shared common ancestor has this character