Transcript Classification of biodiversity - Anoka

5.3 Classification of biodiversity
The Swedish botanist Carolus Linnaeus originally invented
the binomial system to help him consistently name plants
he identified. The system was eventually adopted by other
scientists and remains to the accepted naming system for
species. Though species may have many common names to
avoid confusion scientists always use the
scientific/binomial name.
Essential idea: Species are
named and classified using
an internationally agreed
system.
By Chris Paine
https://bioknowledgy.weebly.com/
http://www.tokresource.org/tok_classes/biobiobio/biomenu/classification/index.htm
Understandings
Statement
5.3.U1
5.3.U2
5.3.U3
5.3.U4
5.3.U5
5.3.U6
5.3.U7
5.3.U8
Guidance
The binomial system of names for species is universal
among biologists and has been agreed and developed
at a series of congresses.
When species are discovered they are given scientific
names using the binomial system.
Taxonomists classify species using a hierarchy of taxa.
Archaea, eubacteria and eukaryote should be
All organisms are classified into three domains.
used for the three domains. Members of these
domains should be referred to as archaeans,
bacteria and eukaryotes. Viruses are not
classified as living organisms.
The principal taxa for classifying eukaryotes are
kingdom, phylum, class, order, family, genus and
species.
In a natural classification, the genus and
accompanying higher taxa consist of all the species
that have evolved from one common ancestral species.
Taxonomists sometimes reclassify groups of species
when new evidence shows that a previous taxon
contains species that have evolved from different
ancestral species.
Natural classifications help in identification of species
and allow the prediction of characteristics shared by
species within a group.
Applications and Skills
5.3.A1
5.3.A2
5.3.A3
5.3.A4
5.3.S1
Statement
Guidance
Classification of one plant and one animal species
from domain to species level.
Students should know which plant phyla have
Recognition features of bryophyta, filicinophyta,
vascular tissue, but other internal details are
coniferophyta and angiospermophyta.
not required.
Recognition features expected for the selected
Recognition features of porifera, cnidaria,
platylhelmintha, annelida, mollusca, arthropoda and animal phyla are those that are most useful in
distinguishing the groups from each other and
chordata.
full descriptions of the characteristics of each
phylum are not needed.
Recognition of features of birds, mammals,
amphibians, reptiles and fish.
Construction of dichotomous keys for use in
identifying specimens.
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U1 The binomial system of names for species is universal among biologists and has been
agreed and developed at a series of congresses.
The 21st International
Congress of Zoology (ICZ)
http://iszscon2012.haifa.ac.il/
http://www.ibc2017.cn/index.html
• Carl Linnaeus originally published Systema Natura in 1758 in which he gave binomials for
all species known at that time.
• The IBC of Vienna in 1905 voted to accept his naming convention.
• Since then both the IBC and ICZ have been the bodies that oversee the international
efforts to maintain consistent naming conventions and use of taxon.
• Periodically the congresses meet to discuss issues affecting classification.
http://www.tokresource.org/tok_classes/biobiobio/biomenu/classification/index.htm
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U2 When species are discovered they are given scientific names using the binomial system.
5.3.U7 Taxonomists sometimes reclassify groups of species when new evidence shows that a
previous taxon contains species that have evolved from different ancestral species.
Historically classification systems
have been revised repeatedly
based on emerging evidence.
Previously in the second half of the 20th century
all living organisms were classified into five
kingdoms. This included prokaryotes being placed
in one kingdom and eukaryotes were split-up into
the remaining four kingdoms.
Recent evidence from genetic
studies of ribosomal RNA has
shown that "prokaryotes" are far
more diverse than anyone had
suspected.
ribosomal RNA is found in all
organisms and evolves slowly so is
a good way to track evolution over
long time periods.
Recent work
http://academic.pgcc.edu/~kroberts/Lecture/Chapter%204/04-23_WhittakerTax_L.jpg
5.3.U4 All organisms are classified into three domains.
Revision of the classification system lead
to a new level of taxon called domains.
The Prokaryotae are now divided
into two domains, the Bacteria and
the Archaea
Bacteria and the Archaea are as
different from each other as either is
from the Eukaryota, the third
domain.
No one of these groups is ancestral to the
others, and each shares certain features with
the others as well as having unique
characteristics of its own.
http://www.ucmp.berkeley.edu/alllife/threedomains.html
5.3.U4 All organisms are classified into three domains.
Features and examples of each domain:
Archaea
Bacteria (Eubacteria)
Eukaryota
Examples are often, but always,
extremophiles:
• Sulfolobus sp. grow in volcanic
springs with optimal growth
occurring at pH 2-3 and
temperatures of 75-80 °C
• Halobacterium sp. (lives in water
with high salt concentrations)
• Staphylococcus aureus (above)
can cause skin infections and
respiratory disease
• Cyanobacteria sp. Are
photosynthetic
• Rhizobium sp. live symbiotically
with plants and fix nitrogen
Includes several kingdoms
including fungi, animals and plants.
Examples range from algae to
Humans.
•
•
•
•
No nuclear membrane
RNA and biochemistry distinct
from bacteria
No nuclear membrane
Nuclear membrane
n.b. viruses are not classified as living organisms in the same way that eukaryotes, archaeans, and
bacteria are. They are however of considerable biological importance.
http://en.wikipedia.org/wiki/Three-domain_system
5.3.U3 Taxonomists classify species using a hierarchy of taxa.
5.3.U5 The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family,
genus and species.
Not all domains use the same taxa – the
example above is for Eukaryotes
5.3.U5 The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family,
genus and species.
5.3.U5 The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family,
genus and species.
5.3.A1 Classification of one plant and one animal species from domain to species level.
Learn a mnemonic, one animal example and one plant example:
Domain
Does
Eukaryota
Eukaryota
Kingdom
Kennard
Animalia
Plantae
Phylum
Play
Chordata
Spermatophyta
Class
Classical
Mammalia
Eudicotyledons
Order
Or
Primates
Magnoliidae
Family
Folk
Hominidae
Ranunculales
Genus
Guitar
Homo
Ranunculus
Species
Songs?
Sapiens
Acris
http://commons.wikimedia.org/wiki/File:Masai_Woman.jpg
http://commons.wikimedia.org/wiki/File:Ranunculus_macro.jpg
5.3.A2 Recognition features of bryophyta, filicinophyta, coniferophyta and angiospermophyta.
e.g.
e.g.
e.g.
e.g.
5.3.A2 Recognition features of bryophyta, filicinophyta, coniferophyta and angiospermophyta.
Bryophytes
(mosses, hornworts
and liverworts)
Filicinophytes
(ferns)
Coniferophytes
(conifer shrubs and
trees)
Angiospermophytes
(flowering plants)
Leaves, roots and stems
Vascular
tissue
Reproductive structures
• No roots, but structures similar to
root hairs called rhizoids
• Mosses have simple leaves and
stems
• Liverworts have a flattened thallus
None
Spores produced in
capsules, which develop
at the end of a stalk
• Roots present
• Short non-woody stems.
• Leaves usually divided into pairs of
leaflets
Yes
Spores produced in
sporangia on the
underside of the leaves
• Roots, present
• Woody stems
• Leaves usually narrow with a thick
waxy cuticle
Yes
Seeds develop from
ovules in female cones.
Male cones produce
pollen.
• Leaves and roots variable in
structure
• Stems maybe woody (shrubs and
trees)
Yes
Seeds develop from
ovules in ovaries, inside
flowers. Seeds are
dispersed by fruits which
develop from the
ovaries.
5.3.A4 Recognition of features of birds, mammals, amphibians, reptiles and fish.
The most familiar animal
from the chordata phyla
belong the to subphylum
vertebrata. Can you
match the different
classes with the images?
Birds
(aves)
Amphibians
(amphibia)
Mammals
(mammalia)
Reptiles
(reptilia)
Fish (Agnatha,
Chondrichthyes, Osteichthyes)
n.b. Fish is not a true class it
is actually a grouping of
three similar classes.
http://commons.wikimedia.org/
5.3.A4 Recognition of features of birds, mammals, amphibians, reptiles and fish.
Mammals
(mammalia)
Reptiles
(reptilia)
Birds
(aves)
The most familiar animal
from the chordata phyla
belong the to subphylum
vertebrata. Can you
match the different
classes with the images?
Amphibians
(amphibia)
Fish (Agnatha,
Chondrichthyes, Osteichthyes)
n.b. Fish is not a true class it
is actually a grouping of
three similar classes.
http://commons.wikimedia.org/
5.3.A4 Recognition of features of birds, mammals, amphibians, reptiles and fish.
A summary of key features that can be used to distinguish between
the vertebrate classes
Limbs
Gas Exchange
Reproduction
Other features
Mammals
4 Pentadactyl
limbs
Lungs with
alveoli
• Internal fertilization
• Give birth to live young
• Mammary glands secrete
milk
• Hairs growing from the skin
• Teeth including living tissue
birds
4 Pentadactyl
limbs, 2 limbs
modified as
wings
Lungs with
parabronchial
tubes
• Internal fertilization
• Hard shells around the
eggs
• Feathers growing from skin
• Beak but no teeth
reptiles
4 Pentadactyl
limbs
Lungs with
extensive
folding
• Internal fertilization
• Soft shells around eggs
• Dry scaly impermeable skin
• Simple teeth – no living
tissue
amphibians
4 Pentadactyl
limbs
Simple lungs
with small
internal folds
and moist
surfaces
• External fertilization in
water
• Protective jelly around
eggs
• Larval stage lives in water
• Soft moist permeable skin
fish
Fins
Gills
• External fertilization in
most species
• Scales grow from the skin
• with a single gill slit
• Swim bladder for buoyancy
5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda
and chordata.
What about other phyla? Can
you match the names with the
images?
cnidaria
annelida
chordata
platylhelmintha
mollusca
porifera
arthropoda
http://commons.wikimedia.org/
5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda
and chordata.
Chordata (animals with a
backbone) should be easy.
Try using the key to help
identify the rest of the
phyla.
5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda
and chordata.
Can you match the phyla with
the images?
cnidaria
mollusca
platylhelmintha
chordata
porifera
annelida
arthropoda
http://commons.wikimedia.org/
5.3.A3 Recognition features of porifera, cnidaria, platylhelmintha, annelida, mollusca, arthropoda
and chordata.
A summary of key features that can be used to distinguish between animal phyla
Symmetry
Segmentation
Digestive tract
Other features
porifera
(sponges)
None
None
No mouth or anus
•
•
•
Porous
attached to rocks
Filter feeder
cnidaria
(corals, jellyfish)
Radial
None
Mouth but no anus
•
•
Stinging cells
Tentacles
platylhelmintha
(flatworms)
Bilateral
None
Mouth but no anus
•
Flattened body
annelida
(earthworms,
leeches)
Bilateral
Very
segmented
Mouth and anus
•
bristles often present
Mollusca
(oyster, snails,
octopus)
Bilateral
Non-visible
segmentation
Mouth and anus
•
Most have shell made of
CaCO3
Arthropoda
(ant, scorpion,
crab)
Bilateral
Segmented
Mouth and anus
•
•
Exoskeleton
jointed appendages
Chordata
(fish, birds,
mammals)
Bilateral
Segmented
Mouth and anus
•
•
•
notochord
hollow dorsal nerve cord
(some have ) pharyngeal slits
5.3.S1 Construction of dichotomous keys for use in identifying specimens.
5.3.S1 Construction of dichotomous keys for use in identifying specimens.
5.3.S1 Construction of dichotomous keys for use in identifying specimens.
5.3.U6 In a natural classification, the genus and accompanying higher taxa consist of all the
species that have evolved from one common ancestral species.
Natural classification groups together species that share a common ancestor from
which they evolved. This is called the Darwinian principle of common descent
It is expected that members of a group share important attributes or
'homologous’ traits that are inherited from common ancestors. For
example Lions share more traits with Jaguars than with Clouded
Leopards.
Grouping together birds, bats and bees because they
fly would be an artificial classification as they do not
share a common ancestor. and evolved the ability to
fly independently.
Plants and fungi were once classified together
because they both possessed shared characteristics
such as cell walls. It is now known that this is an
artificial grouping as their cell walls have a different
molecular biology and they evolved separately.
Natural classification is not straightforward as
convergent evolution can make distantly related
organisms appear similar and adaptive radiation can
make similar organisms appear very different from each
other.
5.3.U8 Natural classifications help in identification of species and allow the prediction of
characteristics shared by species within a group.
Natural classification is very helpful
when dealing with new species:
“New species of legless
amphibian discovered in remote
Cambodian rainforest”
Dichotomous keys can be used to help
identify the species. The keys can place a
specimen with the most closely related
species, genus, family or phyla using
natural classification. To what level of
classification a specimen can be placed
depends on how unique it is.
If a new species of Ant is discovered
then scientists would predict that the
species should possess amongst other
characteristics six jointed legs, a head,
thorax, abdomen, elbowed antennae,
‘antibiotic’ secretory glands. If the
species does not match the expected
set of characteristics this brings into
question either the classification of the
species or of Ants as a family.
http://www.abc.net.au/news/2015-01-17/new-species-of-leglessamphibian-found-in-cambodia/6022048
Bibliography / Acknowledgments
Jason de Nys