“Save the whales. Collect the whole set”
“Plan to be spontaneous tomorrow”
“Ambition is a poor excuse for not having enough sense to be
lazy
U6110 Syllabus: Course Outline• Designed to foster understanding of the structure and
function of land-based environmental systems and their management. The course focuses on an investigation of the mechanisms and interconnections found within and among components of land resource systems and with associated human systems.
• Objectives:– To define an interdisciplinary approach to address land-based
environmental problems and issues.– To develop appropriate skills related to geographical information
systems and database structure/functioning.– To develop skills needed to recognize and analyze the
relationships among the scientific, technological, societal and economic issues that shape environmental research and decision-making.
Populations and Land Use (50% each) Labs: 50% (5 formal labs)
Mostly minds-on experiments with computers. Lab report due (make sure you respect scientific format!)
Final (Inclusive): 30% Quizzes: 10% Field Trip Report: 10%
U6110 Syllabus: Grading (activities)
• Intro to Evolution:“Why the tail can’t wag the dog…”
• Terrestrial Ecosystems & Environmental Science
Today
“The peacock’s tail”: A history of complexity…a) The most complex creatures have tended to
increase in elaboration through time, andb) Humans are, by far, the most complex creatures
of life’s tree
Evolution
“Why the tail can’t wag the dog…”Trends and the proper use of central tendencies:
Evolution of “complexity” in simple organisms
Evolution:Variation vs. Complexity
Forams and the third try
Variation vs. Complexity
In this situation, life’s “mean” complexity may have increased, the “mean” is a terrible measure (and “mode” proper) of “average” or “central tendency” in highly skewed distributions
However There is a constant argument which postulates that an expanding right tail demonstrates a predictable upward thrust of the whole
Variation vs. Complexity
The drunkard’s walk and the law of statistics
Variation vs. Complexity
-) Life has a necessary origin near the left wall (“you can’t precipitated a lion out of the primordial soup”)
-) When there is a necessary origin near the left wall the only way to go is right towards increase in numbers and kinds (increase in variation)
Cope’s Rule and the increase in body size along evolutionary lineages
Variation vs. Complexity
-) Cope’s rule identifies a predominant relative frequency, not an absolute statement.
-) All traditional interpretations of Cope’s rule have been framed in terms of supposed evolutionary advantages for larger bodies (there must be one to survive).
-) The apparent trend is more of increase range of variation rather than absolute size
Cope’s Rule and the increase in body size along evolutionary lineages – Really?
Variation vs. Complexity
During the evolution of forams (for example), there exists no preference for increasing size in speciation event
It seems that Cope’s Rule is driven by an increase in variance rather than a simple directional trend in body size.Size increase, is thus no more than random evolution away from small size.
Variation vs. Complexity
Cope’s other Rule of “the unspecialized” states that founding members of highly successful lineages tend to be small and unspecialized (can tolerate a wide range of environmental conditions and changes) and do not possess complex and highly specific adaptations to narrow behaviors or modes of life (the peacock and the panda).
No directed evolution towards large size or complexity!
Variation vs. Complexity
The most desired ingredient of western comfort rests in finding a clear signal of progress measured as some form of steadily increasing complexity of life as a whole through time.
Progress, however can only be validated by looking at extremes
The modal bacter“Why the tail can’t wag the dog…”
The “upper level attained” is not a measure of organization in general”
There is no direct ancestry between life forms in the sequence of the right tail of complexity!
But does that mean that complexity can’t be driven?
Driven vs. Passive
Both vertebrate and invertebrate fossil records suggest that increasing complexity is passive rather than driven.
Driven vs. Passive
“We are glorious accidents of an unpredictable process with no drive to complexity, not the expected result of evolutionary principles that yearn to produce a creature capable of understanding the mode of its own necessary construction”
The modal bacter and Leonardo’s David
The odds of the human experiment are to phenomenal to replicate…
Human alterations of the Earth System in a simplified way
Human domination of Earth’s Ecosystems
Quantification of human “footprint” show that humans now appropriate 20-60% of life-sustaining resources of the Earth
Human domination of Earth’s Ecosystems
Humans use about 8% of the total primary productivity of the Oceans 25% for upwellings and 35% for continental shelves
Human domination of Earth’s Ecosystems
The modern increase in CO2 represents the clearest and best documented signal of human alteration (30%) of the Earth system.
Changes to global biogeochemical cycles
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1750 1800 1850 1900 1950 2000
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The increase in CO2 is far from being homogeneous(although the atmosphere is a very well mixed fluid!)
Changes to global biogeochemical cycles
Human modification so Earth’s biological resources (its species and genetically distinct populations) is substantial and growing.
“Extinction” and “invasion” are natural processes, but the current rate of loss and of transport is, respectively:- Decreasing genetic/species variability- Homogenizing Earth’s biota
Land transformation and invasion are the two most significant causes of biological extinction.
Biotic Changes
From an evolutionary point of view, humans are negligible forms of life (well, almost…) despite the highest level of complexity attained
From an environmental point of view, humans are central since their impact is unprecedented (temporal and spatial) on Earth
We cannot afford NOT to be anthropocentrists!To maintain the anthropocentric view it becomes paramount to learn how to manage our “land”:
- GIS- Mass/Energy balances (models/empirical)- Studies of critical systems (i.e. forests/peatlands: sources/sinks of CO2)- Agriculture/Biodiversity
Environmental Change
“There is no clearer illustration of the extent of human dominance of Earth that the fact that
maintaining the diversity of “wild” species and the functioning of “wild” ecosystems will require
increasing human involvement!”Vitousek et al. (1997) Science. Vol. 277
Environmental Change
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