scientific naming, cladograms, dichotomous … naming, cladograms, dichotomous keys, taxonomy,...
TRANSCRIPT
Scientific Naming, Cladograms, Dichotomous Keys, Taxonomy, Natural Selection, & Evidence of Common Ancestry
Some organisms have several common names
This cat is commonly known as:
•Florida panther
•Mountain lion
•Puma
•CougarScientific name: Felis concolor
Scientific name means “coat of one color”
Why Scientists Assign Scientific Names to Organisms?
• Binomial Nomenclature - Allows scientists to give each organism a universally accepted two-part name. • The first part of the name is the Genus. • The second part of the name is the Species. • Example: “Homo” is the Genus, “sapiens” is
the species; The scientific name for humans is Homo sapiens
Binomial Nomenclature
Kingdom
Phylum
Class
Order
Family
Genus
Species
Levels of Classification
Most General
Most specific
King Philip came over for good
sweets!
Grizzly bear Black bear Giant panda
Red fox Abert squirrel
Coral snake
Sea star
KINGDOM Animalia
PHYLUM Chordata
CLASS Mammalia
ORDER Carnivora
FAMILY Ursidae
GENUS Ursus
SPECIES Ursus arctos
Hierarchical Ordering of Classification
As we move from the kingdom level to the
species level, more and more members are
excluded – species is least inclusive!
Cladogram• Diagram used to show the evolutionary
relationships among groups of organisms based on derived characteristics.
Derived Characteristics• Evolutionary descent is determined based on
derived characteristics, which are new traits that appear as organisms evolve over time
• The more derived characteristics that they share, the more closely related they are.
Jaws, lungs, claws, feathers, and fur are all examples of derived characteristics!
Dichotomous Keys
• A tool for identifying unknown organisms using a key consisting of paired questions based on observable characteristics.
• Steps:1. Always begin with
the first question2. Answer the paired
questions with yes or no
3. Based on your answers, follow the directions given by the key
Example of a Dichotomous Key
• Identify the unknown insect using the dichotomous key.
Example of a Dichotomous Key
• Identify the unknown insect using the dichotomous key.
Classifying OrganismsOrganisms are divided into 3 domains and 6 kingdoms based on the following characteristics
1. Cell Type: Prokaryotic vs. Eukaryotic• Prokaryotic - No nucleus• Eukaryotic - nucleus
2. Cell Structure: Components of Cell Wall3. Number of cells: Unicellular vs. Multicellular
• Unicellular - One cell • Multicellular - More than one cell
4. Nutrition: Autotrophic vs. Heterotrophic• Autotrophic - makes their own food• Heterotrophic - must consume food
Animalia Kingdom (Domain Eukarya)
• Cell Type: Eukaryotic• Cell Wall: No Cell Wall• Body Type: Multicellular• Nutrition: Heterotrophic• Examples: humans, dogs, sharks, fish, snakes
Plantae Kingdom (Domain Eukarya)
• Cell Type: Eukaryotic• Cell wall contains Cellulose• Body Type: Multicellular• Nutrition: Autotrophic• Examples: corn, ferns, roses, pine tree
Fungi Kingdom(Domain Eukarya)• Cell Type: Eukaryotic• Cell wall contains Chitin• Body Type: Multicellular, except yeast
which is unicellular• Nutrition: Heterotrophic• Are Immobile (cannot move around)• Examples: Yeast, morel, earthstar
puffball, bread mold, mushrooms• All fungi are heterotrophic
decomposers which externally digest dead matter
Protista Kingdom (Domain Eukarya)• Cell Type: Eukaryotic• Cell Wall: Cellulose (some)• Body Type: Unicellular, except algae
which are multicellular• Nutrition: Autotrophic &
Heterotrophic• Are Mobile (can move around)• Examples: Paramecium, euglena,
algae
Eubacteria Kingdom (Domain Bacteria)
• Cell Type: Prokaryote• Cell wall contains Peptidoglican• Body Type: Unicellular• Nutrition: Autotrophic and Heterotrophic• Examples: E. coli, streptococcus, & staphylococcus
Archaebacteria Kingdom (Domain Archae)• Cell Type: Prokaryote• Cell walls do not contain
peptidoglycan• Body Type: Unicellular• Nutrition: Autotrophic &
Heterotrophic• Examples: Live in extreme
environments• Thermophiles – Extreme
temperatures• Halophiles – Extreme salinity
Evolution Occurs by Natural Selection1. Struggle for existence exists in
nature • Competition among members of a species exist for
food, living space, and the other necessities of life.
2. Survival of the Fittest – Individuals that are better suited to their environment – that it, with adaptations that enable fitness –survive and reproduce more successfully; Darwin referred to this as natural selection
Natural Selection• Over time, natural selection
results in changes in the inherited characteristics of a population. These changes increase a species' fitness in its environment.
• Takes place without human control or direction.
• Natural selection cannot be seen directly; it can only be observed as changes in a population over many successive generations.