Zoology The big tsunami….southeast Asia (most recent)….actual picture taken…true survivors

Zoology The Study of Animals

“Specializations” in Zoology Physiology Systematics Entomology Herpetology Ichthyology Mammalogy Ornithology Protozoology Anatomy Cytology Ecology Embryology Genetics Histology Molecular Biology Parasitology *We will be doing more work in the computer lab to find what some of these specializations are all about.

Classification of Organisms Ch.7-Where we will Begin Systematics: The study of the kinds and diversity of organisms and of the evolutionary relationships among them. (AKA: Taxonomy) Nomenclature: The assignment of a distinctive name to each species.

Aristotle 384 BC – 322 BC Wrote History of Animals Classified using hierarchy, "Ladder of Life" Ordered according to complexity of structure and function so that higher organisms showed greater vitality and ability to move.

Carolus Linnaeus Father of Taxonomy 1707-1778 Carl Linnaeus, also known as Karl von Linné or Carolus Linnaeus Father of Taxonomy His system for naming, ranking, and classifying organisms is still in wide use today (with many changes).

A Taxonomic Hierarchy Taxon: Any grouping of animals that shares a particular set of characteristics. Von Linne recognized five taxonomic categories, today we recognize Seven… Can you name any of the 7???

Taxonomic Categories (Broad  Specific) Kingdom Phylum Class Order Family Genus Species Can you give an example of an animal classification from broad to specific?

Common Names Common names are a problem, Why? Crawdad, crayfish, or crawfish??? What do you say? Taxonomy transcends language and country. Common names are not specific.

Assignment of a distinctive name to each species. Nomenclature Assignment of a distinctive name to each species. Binomial Nomenclature (2 names) Von Linne simplified naming: One Latin name to indicate the genus, and one "shorthand" name for species Two names make up the binomial ("two names") species name.

International Code of Zoological Nomenclature The binomial system of nomenclature is universal and clearly indicates the level of classification. No two kinds of animals have the same binomial name. Genus begins with a capital letter, species begins with a lowercase letter, and the entire scientific name is italicized or underlined because it is Latin or Latinized. Ex. Canis familiaris or Canis familiaris

What is a Kingdom? Kingdoms are a part of classification that distinguishes organisms according to cellular organization and mode of nutrition. There are currently 6 kingdoms recognized: Archaebacteria Eubacteria Protista Plantae Fungi Animalia

Kingdom Protista – eukaryotic, unicellular or colonies of Kingdom Protista – eukaryotic, unicellular or colonies of cells, some photosynthetic, some non-photosynthetic We will spend a brief time looking at Kingdom Protista-a refresher from Biology Will include because protists are “animal like” Kingdom Animalia – eukaryotic, multicellular, ingestion, no cell walls All of our time will be spent here! (Hence the course name: Zoology-study of animals )

Animal Systematics (Goal of animal systematics: to arrange animals into groups that reflect evolutionary relationships) 1. Molecular approach – using DNA or RNA 2. Evolutionary relationships – see page 100 Monophyletic Group – one ancestral species Polyphyletic Group – can be traced to separate ancestors (insufficient knowledge) 3. Cladistics - see page 101 & 103 developing cladograms and phylogenetic trees

Patterns of Organization The easiest patterns in organisms is in their body plan Symmetry describes how parts of an animal are arranged around a point or an axis

Radial Symmetry Any plane passing through the oral- aboral axis divides the animal into mirror images (can be modified by arrangement of some structures in pairs, or other combinations around the central axis).

Bilateral Symmetry Arrangement of body parts such that a single plane passing between the upper and lower surfaces and through the longitudinal axis divides the animal into right and left mirror images Characteristic of active, crawling, swimming animals. Cephalization: head Ex. Crayfish Because bilateral animals move primarily in one direction, one end of the animal is continually encountering the environment. Talk about cephalization:these developments result in the formation of a distinct head (called cephalization)

Examples of Bilateral Symmetry:

Asymmetry Arrangement without a central axis or point. Ex. Amoeba

Examples of symmetry:

Terms of Direction See Page 105, Table 7.3

Example: I found this picture online. I did the research and added labels and label lines.

FISH Dorsal fin Dorsal surface Caudal fin Eye Posterior Anterior Pectoral fin Mouth Gill cover Ventral surface Anal fin Ventral or pelvic fin

Please label with the following terms of directions Anterior Posterior Ventral Dorsal Lateral line Oral Caudal Cranial/Cephalic

Dorsal Posterior Anterior Lateral Line Caudal Cranial/Cephalic Oral Ventral

Who Can Label this Guy?

Besides Symmetry, there are other levels of Organization in animals: Unicellular (Cytoplasmic) Level Diploblastic Organization Triploblastic Organization Green: Unicellular: Euglenas Jellyfish: Diploblastic Humans: Triplobastic

Unicellular (cytoplasmic) A body where all the living functions are carried out within the confines of a single cell! (Not simple…think about it…..) These functions must include: locomotion, food acquisition, digestion, water and ion regulation, sensory perception, and reproduction. Examples: Protists Colonies!: Cellular aggregates (colonies) consist of loose associations of cells that exhibit little interdependence, cooperation, or coordination of function. They coordinate on such a small scale that they cannot be considered tissues (group of similar cells acting together to perform a function). In spite of this absence of interdependence, these organisms show some division of labor…some cells may be specialized for reproductive, nutritive, and structural functions

Diploblastic (two) Cells are arranged into tissues (simple tissues) Tissue-level organization 1. Ectoderm: outer body layer (epidermis) 2. Mesoglea: middle layer (may or may not contain cells) 3. Endoderm: inner body layer, the gut (gastrodermis) Body parts are organized into layers derived from two embryonic layers: Ectoderm (gives rise to the epidermis or outer layer-skin) & Endoderm (gives rise to the gastrodermis, the tissue that lines the gut cavity). In between these two layers, there is a middle layer called mesoglea-it may or may not contain cells, when cells are present, is sometimes called mesenchyme. The cells in each tissue layer are functionally independent (work alone) Gastrodermis: digestive and muscular cells Epidermis: epithelial and muscular cells

Diploblastic

Triploblastic (three) Animals with tissues derived from three embryological layers. Most have organ-system level of organization: 1. Ectoderm: outer body layer (epidermis) 2. Mesoderm: middle body layer (supportive, contractile, and blood cells) 3. Endoderm: inner body layer, the gut (gastrodermis) Same as diploblastic organisms in that they have the ectoderm and endoderm, but now the in between layer is called the mesoderm and it actually gives rise to supportive, contractile, and blood cells. Tissues in triploblastic organisms are organized to from excretory, nervous, digestive, reproductive, ciruculatory, and other systems. Usually have bilateral symmetry

Triploblastic Body Plans Pseudocoelomate Coelomate Acoelomate Triploblastic animals are organized into several subgroups based on the presence or absence of a body cavity, and for those that possess this body cavity, the kind of body cavity present. A body cavity is a fluid filled space in which the internal organs can be suspended and separated from the body wall.

Advantages of Body Cavities: Provide more room for organ development Provide more surface area for diffusion of gases, nutrients, and wastes into and out of organs Provide an area for storage Often act as hydrostatic skeletons Provide a vehicle for eliminating wastes/reproductive products from the body Facilitate increased body size

Acoelomate The mesoderm forms a solid mass of cells between the endoderm an ectoderm. Acoelomate: without body cavity….just a mass of cells that are not specialized for a particular function

Pseudocoelomate Has a false body cavity not entirely lined by a mesoderm Pseudocoelomate: False body cavity A body cavity that is not even entirely lined by mesoderm….no muscular or connective tissues are associated with the gut tract, no mesodermal sheet covers the inner surface of the body wall, and no membranes suspend organs in the body cavity. So, the cavity is there, but it really is like a “false” or “fake” cavity because it isn’t even completely there to serve as functional!

Coelomate A true body cavity or coelom that is lined by mesoderm. A thin peritoneum lines the inner body wall and is continuous with the serosa (lining of internal organs). Coelomate: True body cavity So, the body cavity is completely lined/surrounded by mesoderm. Also, this thin mesodermal sheet called the peritoneum lines the inner body wall and is continuous with the serosa which lines the outside of near organs. This peritoneum and serosa suspend visceral structures in the body cavity-give support.

Further Classification….. In this book, the bilaterally symmetrical animals are divided into two large groups: Protostomia Deuterostomia Based on the observation that embryological events may be similar because of shared ancestry

Developmental Embryology A. Protostomes: Early cleavage of zygote Fate of cells is determined early in embryonic development Many protosomes have top-shaped larva (trochophore larva)

Trochophore larva - top-shaped larva

Animal Phyla that are Protostomes Platyhelminthes - flatworms Nematoda - roundworms Mollusca – head-foot plan (like snail, clam, oyster, octopus, squid, nautilus) Annelida – True coelom worms Arthropoda – Jointed exoskeleton (insect, spider, crab, shrimp, centipede)

Developmental Embryology Deuterostomes: Radial cleavage results in cells directly over one another Fate of cells is determined later on in development Gut tract and coelom formation differs Some produce a kidney-bean shaped larval stage (dipleurula) But, there is no single kind of larval stage! (as there was with protosomes-trochophore)

Dipleurula - kidney-bean shaped larval

Animal Phyla that are Deuterostomes Echinodermata – sea stars, urchins, sea cucumbers Chordata – sea squirts, amphioxus, hagfishes, lampreys, sharks, fishes, amphibians, reptiles, birds, mammals

If you discovered a new species….how would you classify it? A Dichotomous Key is a tool that allows the user to determine the identity of items in the natural world, such as trees, wildflowers, mammals, reptiles, rocks, and fish. Keys consist of a series of choices that lead the user to the correct name of a given item. "Dichotomous" means "divided into two parts". Therefore, dichotomous keys always give two choices in each step.

Year 2525 Imagine it's the year 2525. A planet similar to Earth has recently been found in a newly identified solar system in another galaxy. We have sent a space probe with a molecular transport beam to this planet to beam back a variety of different living creatures. Scientists examine the structure of each of these creatures and realize that they need to create a classification scheme to help them compare the alien life forms to each other and discover how they might be related. The lead scientist sends you illustrations of the organisms and asks you to help develop this classification system. Your role is to study the illustrations and come up with a possible classification scheme based on the information provided about each organism. You'll be asked to explain to the scientific team how and why you organized the creatures this way.

How can we tell these aliens apart?

We can classify the aliens by their characteristics.

Your Challenge Your group will be given 16 aliens to classify. Choose one general characteristic to categorize your aliens into two large groups. Ex: has ‘abc’ and does not have ‘abc’. Groups do not have to have the same number of aliens in each. Record your info on the chart provided.

Decide as a Group After you have completed your two groups, split each group into two new groups. Choose one characteristic to separate the first group. Choose one characteristic to separate the second group. You should have 4 groups when completed. Continue splitting each group until you can no longer split them into new categories anymore.

Oh NO! I forgot about these aliens! Where do they go? Can you tell me where you would put them in your classification scheme? Start from the beginning of your chart.