Transcript Organizing Life`s Diversity

Organizing Life’s Diversity
• Classification – the grouping of objects
or information based on similarities.
(ie. organizing your music collection)
(ie: organizing a grocery store)
• Taxonomy – the branch of biology that
groups and names organisms based
on studies of their different
characteristics.
• Today’s phylogenetic classification uses
a hierarchy of taxa to classify
organisms.
• From largest to smallest
help you remember)
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Dear
King
Phillip
Came
Over
For
Greek
Salad
(A mnemonic to
Another way to help you
remember the order, sing the
groups to the tune of
“Yankee Doodle.”
• The phylogeny for a Bobcat is:
Kingdom
Animalia
Phylum
Class
Order
Family
Genus
Speices
Chordata
Mammalia
Carnivora
Felidae
Lynx
Lynx rufus
• The 3 domains are:
– Bacteria
• Prokaryotes
• Cell walls contain peptidoglycan
• Most abundant organism
– Archaea
• Most ancient
• Most closely related to Eukaryotes
• Extremophiles (live in extreme environments)
– Eukarya
• Have membrane-bound nucleus
• Have membrane-bound organelles
• The six kingdoms of organisms are:
– Eubacteria
– Archae
– Protists
– Fungi
– Plants
– Animals
Domain Bacteria
Domain Archae
Domain Eukarya
• Phylogeny – Evolutionary history of a
species.
– Phylogentic species concept defines
species as a cluster of organisms that is
distinct from other clusters.
• Cladistics – a type of classification
system based on phylogeny
(evolutionary history)
• Scientists use a cladogram or
phylogenetic tree to diagram
evolutionary relationships of traits
Phylogeny of Humans
Phylogeny of Humans
• Aristotle - developed the first accepted
system of biological classification
Two groups: Plants and Animals
• Carolus Linnaeus - developed classification
system based on physical & structural
similarities of organisms.
– Still used today
– Includes classification based on structural
similarities & evolutionary relationships of
species.
• Binomial Nomenclature – Two word
naming, developed by Linnaeus to
identify species
– First word = genus
– Second word = species
(ie. Homo sapiens = modern humans)
Note: Scientific names are always
written in italics or underlined
Evolutionary History
• Phylogeny describes the evolutionary
history of a related group of species
• All organisms on Earth evolved from a
single ancestor
• Life on earth began about 3.5 billion years
ago; since that time, new species have
emerged, lived and died out
• New species evolve from pre-existing
species
Fossil Evidence
• Through fossil evidence, physical and
molecular similarities between ancient
species and modern species have
been found.
• Physical and molecular similarities
between diverse species has also
been found.
Extinction
• Organisms try to survive in their
environments through adaptation,
however many species become extinct
• Extinction can occur because of
environmental changes, human
interference or as a result of failure to
adapt to new conditions
Extinction Cont.
• Extinction is a natural and important part of
evolution
• It is estimated that 999 of every 1,000
species that have ever lived on Earth have
become extinct
• The average species survives between 2
and 10 million years
• Even the most highly adapted species
become extinct.
Mass Extinctions
• There have been many mass
extinctions during Earth’s history
• Mass extinction = when more than
50% of species were wiped out
• Mass extinctions make it possible for
new species to develop
• Surviving species are able to diversify
http://www.neok12.com/php/watch.php?
v=zX060c4178075b5f7f7e6663&t=Pre
historic-Animals