An Introduction to Zoology General Information

I. Basics Zoology is the study of the entire animal kingdom (zo- {New Latin} = animal; -ology = study of, knowledge) B. Zoology is a subset of biology C. One of the broadest fields in all of science 20,000 known species of bony fishes 300,000 known species of beetles

II. The Commonality of Living Things A. All are composed of cells (animals are multicellular, heterotrophic organisms) 1. Cell Theory is a basic tenet of biology. The cell theory states that: a) all living things are composed of cells b)  the cell is the fundamental unit of life c)   all cells in our modern atmosphere and conditions must come from pre-existing cells (“omni cellula a cellula” ….Virchow)

B. Genetic Unity 1. All organisms contain heredity information in the same molecule, a nucleic acid called DNA 2.  The DNA of living organisms is remarkably similar. The more closely related two organisms are to each other, the more similar is their DNA 3. The DNA is not only the reason of the genetic continuity of organisms, but it is also the source of genetic and physical diversity through the process of mutation

C. Organisms share a common genetic history – it is termed the evolution of the species 1. Evolution is the unifying theory of biology 2. Evidences for evolution: a) diversity of living and extinct species (currently it is estimated that there is anywhere between 4 to 30 million different species existing today; millions of other species have gone extinct since life began) b) Fossil record…study of paleontology c) Comparative embryology (“ontogeny recapitulates phylogeny”) – the embryonic development of an organism mirrors somewhat its evolutionary history d) Study of DNA and its relatedness between species

e) Molecular biology and the study of proteins in organisms f) Biogeography – the study of the distribution of plants, animals, and fossils throughout the world (Nearctic, Neotropical, Palearctic, Oriental, Australian, Ethiopian) g) Comparative Anatomy 1) homologous structures – structures that are alike anatomically, but function differently 2) analogous structures – structures that have different developmental and anatomical origins, but function similarly (convergent evolution) 3) vestigial structures – anatomical structures that were useful during some time in the species history, but no longer are functional

D. Organisms share same environmental pressures 1.  Organisms must adapt to existing surrounding conditions or face extinction 2.   Ecological problems a)     Pollution of air and water sources b)      Human overpopulation c)      Loss of habitat d)      Global warming issues from human activities e)      Over fishing and over hunting f)       Use of non-renewable fuels (oil, coal, petroleum) g) Decline of rainforests

III. Components of Zoology A. Specialties or sub-disciplines 1.       Study of fish – ichthyology 2.       Study of birds – ornithology 3.       Study of insects – entomology 4.       Study of reptiles and amphibians – herpetology 5.       Study of mammals – mammalogy 6.       Study of mollusks – malacology 7.       Study of spiders – arachnology 8.       Study of one-celled animals –protozoology 9.       Study of parasites – parasitology

Classification the grouping of information or objects based on Taxonomy is the science of grouping and naming organisms. Classification the grouping of information or objects based on similarities.

We only know about a fraction of the organisms that exist or have existed on Earth. Taxonomists give a unique scientific name to each species they know about whether it’s alive today or extinct. The scientific name comes from one of two “dead” languages – Latin or ancient Greek. Why use a dead language?

Devil Cat

Ghost Cat

Mountain Lion

Screaming Cat

Puma

Florida Panther

Cougar

There are at least 50 common names for the animal shown on the previous 7 slides. Common names vary according to region.

Binomial Nomenclature     a two name system for writing scientific names. The genus name is written first (always Capitalized).     The species name is written second (never capitalized).     Both words are italicized if typed or underlined if hand written. Example: Felis concolor or F. concolor Which is the genus? The species?

Categories within Kingdoms Kingdoms are divided into groups called phyla Phyla are subdivided into classes Classes are subdivided into orders Orders are subdivided into families Families are divided into genera Genera contain closely related species Species is unique Categories within Kingdoms

VERTEBRATES (CHORDATES): (1 phylum) THE ANIMAL KINGDOM BASIC CHARACTERISTICS OF ANIMALS: 1. 2. 3. Nine Animal Phyla INVERTEBRATES: VERTEBRATES (CHORDATES): (1 phylum) MULTICELLULAR ORGANISMS CAPABILITY OF LOCOMOTION MUST INJEST FOOD (8 PHYLA) ALL LACK INTERNAL SKELETON, SOME HAVE EXOSKELTON OR SHELL INTERNAL SKELTON MADE OF BONE/ CARTILAGE

Characteristics of Animals 1. Multicellular, eukaryotes 2. Heterotrophs 3. Cells w/out cell walls, many have specialized functions 4. Usually have a method of movement 5. Most reproduce sexually 6. Require oxygen

Describe the Body Plans of Animals 1. Symmetry: balance in body proportions a. Asymmetrical:have irregularly shaped bodies, no symmetry

b. Radial symmetry: can be divided along any plane to produce 2 halves which look alike c. Bilateral: can be divided only one way to produce mirror image halves Radial Bilateral Symmetry Posterior end Dorsal Ventral Planes of Symmetry Anterior end Planes of symmetry

Phylum Porifera Phylum Cnidaria Phylum Platyhelminthes Phylum Nematoda Phylum Annelida Phylum Mollusca Phylum Echinodermata Phylum Arthropoda Phylum Chordata

1. PORIFERA: SIMPLEST ANIMALS NO TISSUE LAYERS EXAMPLES: SPONGES

2. CNIDARIA HOLLOW BODY HAVE STINGING CELLS TWO BODY FORMS MEDUSA & POLYP EXAMPLES: CORAL, JELLYFISH, SEA ANEMONE

3. PLATYHELMINTHES: UNSEGMENTED WORMS FLAT WORMS EXAMPLES: PLANARIA, FLUKE, TAPEWORM UNSEGMENTED WORMS FLAT WORMS

4. NEMATODA UNSEGMENTED WORMS ROUND WORMS EXAMPLES: HOOKWORMS, HEARTWORMS

5. ANNELIDA SEGMENTED WORMS MOST ADVANCED WORMS EXAMPLES: LEECH, EARTHWORMS

6. ARTHROPODA SEGMENTED ANIMALS EXOSKELETONS MADE OF CHITIN CLASS CRUSTACEAN - MARINE ORGANISMS EXAMPLES: SHRIMP, LOBSTER, CRAB, BARNACLE

7. MOLLUSCA SOME HAVE SHELL UNSEGMENTED, SOFT BODIES EXAMPLES: SNAIL, SCALLOP No Shells – Slugs, Squid, Octopus

8. ECHINODERMATA “Spiny Skin” ONLY LIVE IN MARINE ENVIRONMENT EXAMPLES: SEA URCHIN, SEASTAR, BRITTLE STAR

All have Nerve Cord, Notochord, Post anal tail CHORDATA All have Nerve Cord, Notochord, Post anal tail Invertebrate Chordates ->Tunicates, Lancelets Vertebrate Chordates HAVE INTERNAL SKELETON FISH, REPTILES, BIRDS, AMPHIBIANS, MAMMALS

Terms to Know Symmetry Planes through which a body can be cut and have mirror images. Asymmetry No Symmetry Radial Multiple Planes Bilateral 1 plane (midsagital plane)

Terms to Know Dorsal -Back Ventral -Belly Anterior -Head Posterior -Anus Proximal –Closer to midline

Terms to Know Distal –Further from midlin Transverse –Cross section Segment –Unit of the body that is repeated Hydrostatic skeleton –fluid filled structure that resists compression and allows flexing Coelom –fulid filled cavity within a body of an organism