Transcript Document

NATURALIZING the BOUNDARY
between
HUMANITY AND NATURE
photo by priscilla solis ybarra
By
J. Baird Callicott
Professor of Philosophy and
Religion Studies
Institute of Applied Sciences
University of North Texas
Boundaries between humanity and nature in traditional
Western thought are essentially “essentialistic” & metaphysical
Judeo-Christian tradition: “Man” uniquely created in image of God
(a mysterious, non-empirical property, if God not physical)
also (later) uniquely endowed with an immortal soul
Boundaries between humanity and nature in traditional
Western thought are essentially “essentialistic” & quasi-metaphysical
Greco-Roman tradition: Reason (rationality) is “man’s” essence
Plato: mathematized rationality (ratio root of rationality—
the capacity for calculation).
Aristotle defined anthropos as the “rational animal”
Boundaries between humanity and nature in traditional
Western thought are essentially “essentialistic” & quasi-metaphysical
Early Modern Cartesian tradition = J-C + G-R
Rationality is image of God in “man” and immortal element
of human soul.
Descartes connects rationality with creative
use of language, a capacity unique to humans,
even the least intelligent. Parrots seem to use
language, but only reproduce the sounds they
hear and cannot recombine elements to
create novel expressions. Hence, D concludes,
they do not think and therefore they have no
rational (immortal) soul.
Charles Darwin erases the boundary between humanity and
Nature with Descent of Man, in 1872
Argues that such seemingly unique human
capacities as speech, intelligence, even
religion, and ethics, evolved from “nascent”
or “insipient” capacities possessed by
non-human animals, such as complex call
systems among primates (speech), problemsolving skills exhibited by various species
(intelligence), dogs howling at the moon
(religion via superstition), expanded “parental and filial affections”
plus “social instincts and sympathies” (ethics).
Post-Darwinian boundaries between humanity and nature
persist in anthropology—also essentially “essentialistic,”
albeit empirical
(1) Unique use of language proper
(2) Unique use of tools
But . . .
(1) Chimpanzees and gorillas taught use of ASL
(2) Chimpanzees also discovered to make and
use tools—e.g., modified sticks to “fish”
for termites.
Aldo Leopold makes the obliterated boundary between humanity
and nature a cornerstone of his “land ethic”
“It is a century now since Darwin gave us the
first glimpse of the origin of species. We know
now what was unknown to all the preceding
caravan of generations: that men are only
fellow voyagers with other creatures in the
odyssey of evolution. This new knowledge
should have given us, by this time, a sense of
kinship with fellow creatures . . . [and] a wish
to live and let live.”
“A land ethic changes the role of Homo sapiens
from conqueror of the land community to plain
member and citizen of it. It implies respect for his fellow members
and also respect for the community as such.”
Also following Darwin, Leopold takes community membership to
be the foundation of ethics (and environmental ethics)
“As man advances in civilization, and small
tribes are united into larger communities, the
simplest reason would tell each individual that
he ought to extend his social instincts and sympathies to all the members of the same nation,
though personally unknown to him.”—CD
“All ethics so far evolved rest on a single
premise: that the individual is a member of a
community of interdependent parts.”—AL
Evolutionary biology and ecology “simply enlarges the boundaries
of the community to include soils, waters, plants, and animals, or
collectively: the land.”—AL
But the erased boundary between humanity and nature has
paradoxical consequences for the Leopold land ethic
“To be a part, yet to be apart; to be a part of the
land community; yet to view or see oneself as a
part of that community (and thus to remain apart
from it)—that is the dilemma. . . . If man is a
plain member and citizen of the land community,
one of thousands of accretions to the pyramid of
life, then he cannot be a nonmember and
conqueror of it; and his actions (like the actions of
other organisms) cannot but express his position
within the pyramid of life.”—Peter Fritzell
If Homo sapiens is a part of nature then human actions, no less than
the actions of other species, are natural—just another intriguing
chapter in the biography of the Earth, no more subject to ethical
praise or condemnation than the actions of other species.
The erased boundary between humanity and nature is especially
confounding and vexing for contemporary conservation biology
What to conserve?: Biodiversity. But . . . can be humanly
“enhanced” or increased locally by adding exotic species.
What is an “exotic species?”: One that got to where it is by human
agency—whether intentional or unintentional—Reed Noss.
Alternative conservation goal: biological integrity. What is that?:
A biotic community approaching a condition of naturalness, i.e.,
free of human influence—Paul Angermeier and James Karr
“Nothing in biology makes sense except in the light of evolution”
—Theodosius Dobzhansky (quoted with approval by Gary Meffe)
But in light of evolution, human beings are a part of, not apart from
nature.
The philosophical challenge to environmental ethics and conservation
biology: preserve the boundary between humanity and nature, but
do so consistent with the foundational implications of Darwinism.
Biotic communities composed of species populations.
Ecosystems composed of processes—such as energy flows (photosynthesis and metabolism) and nutrient cycles (nitrogen, calcium)—
of which organisms of various species are agents.
Key concept: natural boundaries (“surfaces”) emerge at the interface
between processes occurring on different temporal scales—T.F.H.
Allen and T. W. Hoekstra
“The landscape is hierarchically structured by a small number
of processes into a number of nested levels, each of which has
its own physical textures and frequencies. That is, the processes that
generate discontinuous time dynamics also generate discontinuous
physical structure.”—C.S. Holling
Photosynthesis—individual tree.
Ecological succession—group of trees (woods);
Disturbance regimes—patchy landscape, such as oak savanna.
Climate —biomes (desert, forest, prairie, tundra)
Temporal scales suggested by C. S. Holling
in “Cross-scale Morphology, Geometry,
and Dynamics of Ecosystems,” each driven by
various biological and suprabiological processes.
1. the “vegetative” (organismic) temporal scale
(photosynthesis and metabolism)
2. the ecological temporal scale
(succession and disturbance)
3. the climatic temporal scale
(mean annual temperature & moisture fluctuations)
4. the evolutionary temporal scale
(adaptation, speciation, extinction)
5. the geo-morphological temporal scale
(plate tectonics, up thrust, erosion, rock cycle)
C. S. Holling identifies several major temporal scales set by
various biological and suprabiological processes.
Photosynthesis and metabolism: the
“vegetative” or organismic scale.
Diurnal (alteration of light and
dark); annual (seasonal alteration of
growth and dormancy / life cycle of
annual plants / decomposition of
detritus); decadal (life cycle of
shrubs and scrubby trees); centennial
(life-cycle of long-lived trees)
Scale = @ 1 day - 1000 years
C. S. Holling identifies several major temporal scales set by
various biological and suprabiological processes.
Succession and disturbance: the ecological scale. Annual
(herbaceous annuals —> perennial weeds —> shrub and scrub);
decadal (shrub/scrub —> forest // fire, flood, high-wind, grazing,
disease, insect-irruption // animal
population cycles); centennial
(second-growth forest —> old
growth // fire, flood, high-wind,
disease, insect-irruption;
millennial (old growth —> climax)
Scale = @ 1 year - 5,000 years
C. S. Holling suggests several major temporal scales set by
various biological and suprabiological processes.
Fluctuations in temperature and rainfall: the climatic temporal scale
Centennial at regional spatial scale (decade-long warmer/colder,
wetter/dryer periods do not count as climate change, but “Little Ice
Age” [1550-1850] does); millennial at global spatial scale (last glacial
incursion began to end 14,000-16,000); multi-millennial (Pleistocene
began 2-3 million years ago and includes 4 major pulses, punctuated
by interstadials; and Pleistocene 1 of 6 sets of glacial epocs occurring
at roughly 925, 800, 680, 450, 330, and 2-3 million years BP).
Scale = @ 3-5 C yrs - 3-5 K yrs (regional)/1 K yrs - 3-5 M yrs (global)
Complicated by seasonality: the climates of Houston and El Paso
are differentiated more by avg. ann. rainfall (H = @ 48” / EP = @8”)
than temp. (H = @ 69F / EP = @ 64F), but the climates of Dallas and
Seattle, while temperature differences are significant (D =@65F /
S = @53F), rainfall is @ the same (D = @ 33” / S = @ 36”).
C. S. Holling identifies several major temporal scales set by
various biological and suprabiological processes.
Adaptation, speciation, extinction: the evolutionary temporal
scale. Decadal/centennial (some insects can speciate after several
hundred generations), millennial (Homo sapiens sapiens has
existed 100,000 - 200,000 years), multimillennial (average life-span
of vascular plant & vertebrate animal spp is 1 million years); sharks
extant for 100 million years.
Scale = @ 10 thousand - 10 million yrs
(ignoring outliers such as rapidly
evolving insects and the incredibly
long-lived sharks)
C. S. Holling identifies several major temporal scales set by
various biological and suprabiological processes.
Plate tectonics, up thrust, weathering,
and the rock cycle: geo-morphological
temporal scale. Millions of years
(mountain up thrust—15 million years
at plate movement rate of 2-15 cm per
year; mountain weathering—100
million years); billions of years (rock
cycle: spreading from deep ocean
seams, plate migration, up thrust,
weathering, sedimentation, subduction,
melting.)
scale = @ millions to billions of years
Boundary conditions at the interface of temporal scales
Albeit themselves dynamic, up-scale processes may be regarded as
stable vis-à-vis down-scale processes.
Examples (1): “The Pacific plate is moving north relative to the North
American plate at a rate of approximately 5 cm/year. . . .As a result,
Los Angeles, now more than 500 km south of San Francisco is
moving slowly toward that city. If this motion continues, in about 10
million years San Francisco will be a suburb of Los Angeles.”
— D. B. Botkin and E. A. Keller This geomorphological process has
had no effect on the organismic-scaled California real estate market.
Example (2): Canada is increasing in elevation (rebounding from the
weight of Pleistocene ice) and moving northwest with the North
American plate. An ecologist studying the population dynamics of
snowshoe hare and arctic fox at the ecological temp. scale may regard
the elevation and latitude / longitude of her study site as unchanging.
Boundary conditions at the interface of temporal scales
Up-scale processes “constrain” down-scale processes
Example (1): climate constrains processes at the organismic and
ecological scales—(A) plants grow more slowly in (a) colder &
(b) dryer climates; (B) diversity increases progressively with
warmer / wetter climates from arctic to tropical latitudes.
Example (2): disturbance regimes at the ecological scale constrain
processes at the organismic scale—(A) seasonal flooding in the
Colorado River is necessary for the reproductive success of the CR
Squawfish; (B) periodic fires and herbivory prevent the growth of
woody vegetation on prairies.
Boundary conditions at the interface of temporal scales
Down-scale processes are often constitutive of up-scale processes
Ex (1): weather (diurnal / seasonal / annual fluctuation of temp
& rainfall) constitutes climate.
Ex (2): plant growth and reproduction on the organismic
temporal scale constitutes succession on the ecological temporal
scale.
Boundary conditions at the interface of temporal scales
Down-scale constitutive processes are damped down and averaged
out as they cross the border to constitute up-scale processes
Ex (1): the diurnal, seasonal, and annual vagaries of local weather
are averaged (to annual rainfall and temperature) as they
constitute regional climate. Pulses of hard rain or lack thereof
(drought)—both common in US SW—and temperature fluctuations
(heat waves / cold snaps) are damped as they constitute climate.
Ex (2): The vagaries of mortality and replacement of individual
trees constituting an old growth or climax forest are averaged out
and damped down as the border between the organismic and ecological temporal scale is crossed.
Boundary conditions at the interface of temporal scales
Changed rates of constitutive downscale processes can storm across
the border and alter up-scale processes
Ex (1): traditional scattered swidden agriculture in Amazon rain
forest is at a spatio-temporal scale comparable to individual tree
mortality and replacement; wholesale clearing for cattle pasture
threatens to alter regional climate. Reduced forest cover—>reduced
transpiration—>reduced atmospheric moisture—>reduced annual
rainfall = regional climate change.
Ex (2): fire suppression and livestock grazing (changes in disturbance
regimes at lower end of ecological temporal scale) in US Southwest
“flipped” region from grassland to scrub (at higher, successional end
of the ecological temporal scale).
The natural temporal boundary between humanity and nature
Homo sapiens sapiens speciated on the evolutionary temporal scale.
Hss evolved “euculture” (C. Lumsdon and E. O. Wilson) on the
same scale, while some other species may have evolved (at best)
“protoculture.”
Hss and human culture are, thus, both natural, having evolved by
Darwinian processes (chance variation & natural selection).
The natural temporal boundary between humanity and nature
“Man receives and transmits . . . not one
but two heredities, and is involved in two
evolutions, the biological and the
cultural.”—T. Dobzhansky
Information transmission is the means of
both. Biological—genetic information encoded in chromosomes; cultural—memetic
information encoded in symbols and signs.
Euculture (sensu Lumsden and Wilson),
uniquely among human beings,
having once evolved, took over the task of subsequent adaptation
to various habitats.
The natural temporal boundary between humanity and nature
But cultural “evolution” is Lamarckian—proceeding by the transmission of acquired characteristics to future generations—not Darwinian.
And the temporal scale of Lamarckian cultural
evolution is many times faster than Darwinian
biological evolution.
Plus it is currently accelerating.
Use of atlatl & spear common @ 25-30 K BP; bow & arrow @ 1520 K BP; cross bow 4th century BCE in China, 10-11th century AD
in Europe; firearms used in Europe in 14th century; breech-load rifle
mid-19th century; automatic firearms mid-20th century.
The natural temporal boundary between humanity and nature
Temporal scale of cultural evolution
@ 1 yr - 10 thousand yrs
Temporal scale of biological evolution
@ 10 thousand - 10 million yrs
1C 1K
yrs
10-20K yrs
The natural temporal boundary between humanity and nature
“Human activity becomes unnatural when it
involves technology.”—Paul Angermeier
On the face of it, a variation of essentialism:
“technology” another word for “tool-use.”
“Human activities that exceed our genetically
evolved—as opposed to culturally evolved—
abilities are unnatural.”—PA
But why?
The natural temporal boundary between humanity and nature
“Humans are cultural as well as biological animals. For conservation,
the most important outgrowth of culture is technology, with which we
transform nature . . . . Because technological [and more generally
cultural] evolution is much more rapid than genetic evolution, we
transform ecosystems faster than other biota can adapt.”—PA
The natural / unnatural paradox resolved: Human beings are natural
because we evolved as a species, just as any other species, in accord
with Darwinian principles. But we became unnatural because culture
took over the process of adaptation to the environment and the
temporal scale of Lamarckian cultural evolution is very rapid in comparison with the temporal scale of Darwinian biological evolution.
In effect, Homo sapiens sapiens stepped across a temporal boundary.
The natural temporal boundary between humanity and nature
Another paradox resolved: it seems intuitively obvious that our
distant Homo sapiens sapiens ancestors were more natural than we.
But this difference cannot be accounted for on “essentialist” grounds:
as the species HSS they were equally created in the image of God,
rational, language-using, tool-using (technological) . . . .
Early HSS culture evolved more slowly than modern and contemporary culture. The high end of the temporal scale of cultural evolution is sufficiently in phase with the low end of the temporal scale of
biological evolution for the former not to storm across the border and
disrupt the latter.
The natural temporal boundary between humanity and nature
May explain why African relatives of American Pleistocene megafauna not also extinct: Had time to adapt (biologically) to human
cultural adaptations.
Implications for conservation biology, environmental ethics, and
environmental justice
Conservation biology: the vital distinctions between natural & unnatural disturbance/change and between native & exotic spp rescued
w/out resort to metaphysical and quasi-metaphysical essences.
Environmental ethics: the spatio-temporal scale of human changes
imposed on nature can replace the old Leopoldian norm of
“integrity, stability, and beauty of the biotic community.” A thing
is right when it tends to disturb ecosystems at fitting spatio-temporal
scales. It is wrong when it tends otherwise.
Environmental justice: While we may celebrate contemporary
peoples living by means of older, less rapidly evolving technologies
as more natural, we must ask if they have a choice in the matter.
THE END
THANK YOU for YOUR
ATTENTION and PATIENCE