Transcript Zoology - Images

Zoology
Zoology
The Study of
Animals
“Specializations” in Zoology
*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
• 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
Can you give an
example of an animal
classification from
broad to specific?
Family
Genus
Species
Common Names
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
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 oralaboral 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
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.
Dorsal fin
Dorsal surface
Caudal fin
Eye
Posterior
Anterior
Pectoral fin
Mouth
Gill cover
Ventral surface
Ventral or pelvic fin
Anal fin
Please label with the following
terms of directions
•
•
•
•
•
•
•
•
Anterior
Posterior
Ventral
Dorsal
Lateral line
Oral
Caudal
Cranial/Cephalic
Dorsal
Anterior
Lateral Line
Posterior
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
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
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)
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)
Triploblastic Body Plans
Pseudocoelomate
Acoelomate
Coelomate
Advantages of Body Cavities:
1. Provide more room for organ development
2. Provide more surface area for diffusion of gases, nutrients, and wastes into
and out of organs
3. Provide an area for storage
4. Often act as hydrostatic skeletons
5. Provide a vehicle for eliminating wastes/reproductive products from the body
6. Facilitate increased body size
Acoelomate
• The mesoderm forms a solid mass of
cells between the endoderm an
ectoderm.
Pseudocoelomate
• Has a false body cavity not entirely
lined by a mesoderm
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).
Further Classification…..
• In this book, the bilaterally symmetrical
animals are divided into two large groups:
1. Protostomia
2. 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
• Phyla:
– 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
• Phyla:
– 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.
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.