Transcript Classification of Or..

Classification
… of organisms
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Scientists discover new species of
organisms nearly every day.
Most these species live in regions
difficult to access, such as tropical
forests and the oceans.
It is necessary to classify these
organisms in order to better
understand them.
What is it?
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Classification is the action of
grouping objects into useful units.
Taxonomy is the science of
classifying organisms. It consists in
classifying organisms according to
different sources of information.
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Sometimes the characteristics used
for classification can vary.
Aristotle (384-322 BC)
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Was one of the first
taxonomists.
He classified plants into
grasses, bushes, and trees.
He classified animals depending on
whether they lived on the earth, in
water, or in the air. (BUT - It didn't explain
the fact that some birds live in the water and
the air.)
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To identify an animal, it is not
necessarily useful to know that it has
some wings.
It would be artificial to group the
animals while only focusing on the
fact that they have wings.
Carolus Linnaeus (1707-1778)
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Was a Swedish botanist who
created a system of grouping
by classification that is still
used today.
Based it on physical
characteristics.
Established binomial nomenclature in Latin,
so all scientists can understand it, no matter
what their language is.
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In taxonomy, the organisms are
grouped in a set of categories. The 7
groups are:
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Kingdom
Phylum
Class
Order
Family
Genus
Species
Each of these categories includes the
previous category.
In other words…
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A family is a group of related Genus,
an order is a group related families, a
class is a group related orders, a
phylum is a group of related classes,
and a kingdom is a group of related
phyla.
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One of the objectives of the modern
taxonomy is to establish a natural
classification founded on evolution.
One supposes that the related
organisms have more features in
common than the distantly related
organisms.
Binomial Nomenclature
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A set of scientific names formed by two
words. The first term designates the
Genus (a group of similar species), and
the second designates the species.
The Genus is written with a capital and
the species with a lower-case letter and
the two names are in italic or underlined.
Ex. sugar maple  Acer saccharum
or  Acer saccharum
Where do humans fit in?
Categories
Example
English
kingdom
Animal
Animal
Phylum
Chordata
Chordates
class
Mammalia
Mammalian
order
Primates
Primates
family
Hominidea
Hominid (fossil and modern
human forms)
genus
Homo
Modern humans and close
relatives
species
Homo sapiens
Humans
Phylogeny and Phylogenetic trees
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Phylogeny is the history of the
evolution of the species.
Scientists compared some modern
shapes to fossils of similar shapes.
According to the biologists, new
species appeared as the organisms
adjusted (evolved) and the
populations changed.
The representation of this classification
looks like the tree below:
How to read a phylogenetic tree:
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Modern species are indicated at the
end of the branches.
Any groups closer together in the
tree have a lot of common features
Any distant groups are very
different and are probably not
closely related.
Classification Activity
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In groups arrange the following organisms into
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Categories
And then sub-categories
Base your choices on physical characteristics,
behavior, or some other criteria.
Each group will have to explain their decisions
that lead to their classification
Alligator, bat, beaver, Bluefin tuna, crocodile,
E. coli (bacteria), English oak (tree), mouse, owl,
parrot, Reef shark, Red maple (tree), Red oak
(tree), Salmonella (bacteria), tiger, Tiger
shark, whale, Yellowfin tuna