Diversity and how it is produced

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Diversity and how it is produced
1. Naming organisms and its scientific basis
2. Evolution of plant Phyla in relation to
geological time
3. Selection
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1. Naming organisms and its scientific basis
Linnaeus and binomial classification
Cladistic analysis
The hierarchical naming system
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Carl Linnaeus 1707-1778
Linnaeus and binomial classification
Carl Linnaeus 1707-1778
Swedish naturalist and explorer
Binomial classification of species using Latin
names. Based on sexual characteristics
Catnip was known as 'Nepeta floribus interrupte
spicatis pedunculatis' Linnaeus abbreviated it
to 'Nepeta cataria' literally, pertaining to
cats.
Use of type specimens
Latin descriptions
Authorities Nepta cataria L.
http//www.nrm.se/fbo/hist/linnaeus/linnaeus.html.
en
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Cladistic analysis
In-group and out-group
Primitive characters
Derived characters
Parsimony
Use of molecular methods
Fig. 15.13A
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The hierarchical naming system
Page 306
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Fig 15.10
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2. Evolution of plant Phyla in relation to
geological time
A. The pattern of plant evolution
B. Major events in geological time
C. Continental drift
D. Major extinctions and the trend in numbers of
families
E. Plant-environment interaction
F. Atmospheric CO2 concentration and evolution
G. Environmental influences at the
Triassic-Jurassic extinction
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Background points of interest
Over the last 450 million years (Phanerzoic
Period) fossil evidence indicates that about 90
of land species have become extinct
The average life of a fossil flowering plant
species is about 3.5 million years
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Fig 17.3A
A. The pattern of plant evolution
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Approximate numbers of plant species
Nonvascular plants (Bryophytes)
Mosses
12,000
Liverworts
6,500
Vascular plants
Seedless plants
Lycophytes
1,000
Horsetails
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Ferns
12,000
Seed plants
Gymnosperms
Conifers
550
Cycads
100
Ginko
1
TOTAL
Angiosperms
282,350 app
Anthophyta
250,000
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Geological time scale
B. Major events in geological time
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C. Continental drift
Permian extinctions
Fig 15.3B
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Continental drift
Fig 15.3A
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The rise in the number of families
D. Major extinctions and the trend in numbers of
families
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The environment influences plants
Temperature
Radiation
Water
Soil
E. Plant-environment interaction
Plants influence the environment
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Plants influence the environment
The environment influences plants
Temperature
Radiation
Water
Soil
Plants influence the environment
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On geological time scales
On geological time scales
Dynamics of the carbon cycle are dominated by
weathering and deposition of organic carbon
stored in rocks, e.g., limestone containing
calcium carbonate
Deposition of layers of organic matter that
become fossil fuels
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Carbon dioxide through geological time
Permian extinctions
Cretaceous extinctions
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G. Environmental influences at the
Triassic-Jurassic extinction
Major periods of plant and animal extinctions
rarely overlap
Major extinctions of marine and terrestrial
animals and changes, but not large numbers of
extinctions in plants
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The late Triassic
Very large reduction in leaf size during the late
Triassic
Indicates an increase in temperature?
Triassic
Jurassic
Parallel reductions in stomatal density suggest
increase in CO2 concentration. Estimated
doubling of CO2 and 4oC temp increase
CO2 came from volcanic activity due to the break
up of Pangea?
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Three conclusions and a question about evolution
Three conclusions and a question about evolution
of plant Phyla in relation to geological time
The environment has shown marked changes over
geological time
Geological processes and plants have interacted
to produce some of these changes
Major plant phyla have evolved at distinct times
in the earths history
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Sections you need to have read
15.1 15.2 15.3 15.10 15.11 17.2 17.3
Courses that deal with this topic
Biology 102 General Biology
GEOL 101 Introduction to Geological Sciences