INTRODUCTION TO ZOOLOGY:  INVERTEBRATES

Grouping & Identifying Living Things  These are animals without a backbone
 There are eight groups of invertebrates:
WHAT IS ZOOLOGY? • Molluscs
 It is the study of animals • Flatworms
 Zoology- zoon, animal + logos, to study • Annelids
WHY STUDY ZOOLOGY? • Roundworms
 Learn about animals • Sponges
 Learn about animal interactions with each other, with other species, • Echinoderms
and with their environment. • Cnidarians
HOW DO WE STUDY ANIMALS?
• Arthropods
 Use Scientific Methods
1. MOLLUSCS
 Problem
 Research  Crawl on a single fleshy pad.
 Hypothesis  Can have a shell
 Experiment 2. FLATWORMS
 Result  Have flat worm like bodies
 Conclusion 3. ANNELIDS
WHY CLASSIFY?  Have round worm like bodies
• Think of three examples where we group things.  Have bodies divided into segments
• Why do we group these things? 4. ROUNDWORMS
CLASSIFYING LIVING THINGS  Have long thin round worm like bodies
 We put livings things into two large groups:  Have bodies with no segments
 Animals 5. SPONGES
 Plants  Have bodies made of loosely joined cells
 ANIMALS 6. ECHINODERMS
 Animals are spilt into two major groups:  Have bodies divided into five parts
 Vertebrates  Have spiny outer covering
 Invertebrates 7. CNIDARIANS
 VERTEBRATES  Have thin sack like bodies
 These are animals with a backbone.  Have tentacles
 There are five groups of vertebrates: 8. ARTHROPODS
• Amphibians  Have lots of legs and segmented bodies.
• Birds  There are four group of arthropods:
• Fish • Arachnids
• Mammals • Centipedes & Millipedes
• Reptiles • Crustaceans
1. AMPHIBIANS • Insects
 Have moist skin
 Lay jelly coated eggs in water ARTHROPODS - ARACHNID
 Lives on land and water  Have four pairs of legs.
2. BIRDS/AVES  Have bodies divided into two sections
 Have feathers and hollow bones ARTHROPODS – CENTIPEDES & MILLIPEDES
 Lay hard shelled eggs  Have long thin bodies and pairs of legs on each of their many body
 Warm blooded sections
3. FISH ARTHROPODS - CRUSTACEAN
 Have wet scales  Have five-seven pairs of legs
 Lays eggs in water  First pair often used as pincers
 Lives in water  Bodies covered in shell
4. MAMMALS ARTHROPODS - INSECTS
 Have hair and produce milk  Have three pairs of legs
 Give birth to live offspring (no eggs)  Bodies divided into three sections
 Warm blooded  Often have wings
5. REPTILES
 Have dry scales
 Lay leathery shelled eggs
 Cold blooded

SUMMARY OF VERTEBRATES
AMPHIBIANS MOLLUSCS SPONGES

ECHINODERMS

BIRDS/AVES FLATWORMS

CNIDARIANS

ARTHROPODS – ARACHNID ARTHROPODS – CENTIPEDES & MILLIPEDES

FISH ANNELIDS

ARTHROPODS – CRUSTACEAN ARTHROPODS - INSECTS

MAMMALS ROUNDWORMS

REPTILES
 CLASSIFICATION  Modern biologists group organisms into categories representing
lines of evolutionary descent.
The Challenge  Species within a genus are more closely related to each other than
 Biologists have identified and named approximately 1.5 million to species in another genus.
species so far.  E.g. Genus: Felis; Genus: Canis
 They estimate that between 2 and 100 million species have yet to
be identified. Similarities in DNA and RNA
 Scientists use and differences in DNA to determine classification
Finding Order in Diversity similarities and evolutionary relationships.
1. Why Classify?  They can sequence or “read” the information coded in DNA to
 To study the diversity of life compare organisms.
 To organize and name organisms Kingdoms and Domains
2. Why give scientific names?  In the 18th century, Linnaeus originally proposed two kingdoms:
 Common names are misleading Animalia and Plantae.
 E.g. jellyfish, silverfish, starfish; these animals are NOT fish  By the 1950s, scientists expanded the kingdom system to include
five kingdoms.
Why Scientists Assign Scientific Names to Organisms?
 Some organisms have several common names The Six Kingdom System
 This cat is commonly known as:  In recent years, biologists have recognized that the Monera are
composed of two distinct groups.
 As a result, the kingdom Monera has now been separated into two
kingdoms: Eubacteria and Archaebacteria, resulting in a six-
kingdom system of classification.
The Three-Domain System
•Florida panther  Scientists can group modern organisms by comparing ribosomal
•Mountain lion RNA to determine how long they have been evolving independently.
•Puma  This type of molecular analysis has resulted in a new taxonomic
•Cougar category—the domain.
Scientific name: Felis concolor
Scientific name means “coat of one color” The Three Domains
 The three domains, which are larger than the kingdoms, are the
Origin of Scientific Names following:
 By the 18th century, scientists realized that naming organisms with o Eukarya– protists, fungi, plants and animals
common names was confusing. o Bacteria– which corresponds to the kingdom Eubacteria.
 Scientists during this time agreed to use a single name for each o Archaea– which corresponds to the kingdom
species. Archaebacteria.
 They used Latin and Greek languages for scientific names.
CLASSIFICATION OF LIVING THINGS
Linnaeus: The Father of Modern Taxonomy - The three-domain system
Bacteria  Archaea  Eukarya
1732: Carolus Linnaeus developed system of classification - binomial
nomenclature - The six-kingdom system
a. Two name naming system Eubacteria  Archaebacteria  Protista  Plantae  Fungi  Animalia
b. Gave organisms 2 names
Genus (noun) and species (adjective) KINGDOM ARCHAEBACTERIA
Cell Type Prokaryote
Rules for naming organisms Number of Cells Unicellular
1. Written is Latin (unchanging) Nutrition Autotroph or Heterotroph
2. Genus capitalized, species lowercase Extreme Environments
3. Both names are italicized or underlined Location Volcanoes, Deep Sea Vents,
Yellowstone Hot Springs
EX: Homo sapiens: wise / thinking man
Examples Methanogens Thermophiles

Linnaeus’s System of Hierarchy

Least specific Most specific
Kingdom  Phylum  Class  Order  Family  Genus  Species

1. Which of the following contains all of the others?

a. Family b. Species c. Class d. Order
2. Based on their names, you know that the baboons Papio annubis and
Papio cynocephalus do not belong to the same:
a. family b. Genus c. Order d. Species KINGDOM EUBACTERIA
Cell Type Prokaryote
Binomial Nomenclature Example Number of Cells Unicellular
 For example, the polar bear is named Ursus maritimus. Nutrition Autotroph or Heterotroph
 The genus, Ursus, describes a group of closely related bear Examples Streptococcus, Escherichia coli (E. coli)
species.
 In this example, the species, maritimus, describes where the polar
bear lives— on pack ice floating on the sea.
Modern Classification
 Linnaeus grouped species into larger taxa, such as genus and
family, based on visible similarities.
 Darwin’s ideas about descent with modification evolved into the
study of phylogeny, or evolutionary relationships among organisms.
KINGDOM PROTISTA - The “Junk-Drawer” Kingdom
Cell Type Eukaryote
Number of Cells Most Unicellular, some multicellular
Nutrition Autotroph or Heterotroph
Examples Amoeba, Paramecium, Euglena,

KINGDOM FUNGI - Most Fungi are DECOMPOSERS

Cell Type Eukaryote
Number of Cells Most multicelluar, some unicelluar
Nutrition Heterotroph
Examples Mushroom, yeast, mildew, mold

KINGDOM PLANTAE
Cell Type Eukaryote
Number of Cells Multicellular
Nutrition Autotroph
Examples Mosses, ferns, conifers, flowering plants

KINGDOM ANIMALIA
Cell Type Eukaryote
Number of Cells Multicellular
Nutrition Heterotroph
Examples Sponges, worms, insects, fish, mammals