Second Exam ThursdayChapters 10, 11, 12, 13, 14, and 15 (most)Can humans share spaceship earth?

Why Can't We Humans Share Spaceship Earth?

The Vanishing Book of Life on Earth

Watch Average Temperatures 1884-2012

Global Warming

Watch Domino Effects Also Handouts 5, 6, and 7

Intelligent Design?

Space Travel

Agriculture

Economics

Kc = 160Kb = 125

Nc* = 70Nb* = 30

Nc* = Kc – cb Nb* cb = (Kc – Nc*)/ Nb* = (160 – 70)/30 = 90/30 = 3.00

Nb* = Kb – bc Nc* bc = (Kb – Nb*)/ Nc* = (125 – 30)/70 = 95/70 = 1.357

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Experimental Ecology

Controls, replicates, treatments, pseudoreplication

Marine rocky intertidal, space-limited systems

Joe Connell, barnacles, Balanus and Chthamalus

Bob Paine, mindless experiments, Pisaster removal, keystone predator

Bruce Menge, removal + addition experiment with sea stars

Art Dunham, Big Bend Grapevine hills, lizard removal experiments

Jim Brown, New Mexico seed eating ants and rodents

2 replicates for each of 12 treatments

(including 11 manipulations plus 2 controls).

Short term: ants and rodents compete for seeds

Large seeded plants versus small seeded plants

Long term: indirect mutualism, facilitation between ants and rodents

Simberloff and Wilson’s defaunation experiments in Florida keys

Non-interactive, interactive, assortative, and evolutionary equilibria

Predation

Skutch’s naïve group selection perspective

Peregrine falcon and starling flocks

Frazzetta’s snake strike 3/100ths of a second

Holling’s preying mantids

Lotka-Volterra Predation Equations

“The recognition that animals can hold their rate of reproduction belowthe maximum that is possible for them throws fresh light upon thatmost hideous blot on the fair face of nature, predation, the killing anddevouring of one creature by another. It is well known that if predatorsare suddenly removed, the animals on which they preyed may becomeso numerous that they exhaust their food supply, with tragic conse-quences not only to themselves but to other associated animals. Thisis particularly striking in the case of large herbivores which, in the absence of checks upon their increase, may so overbrowse or overgrazetheir range that, even after their removal it takes years to recover.Hence predation is frequently regarded as a blessing in disguise,necessary to preserve the health and balance of a natural community.But, if animals can adjust their reproduction to the mortality of theirspecies, it follows that, if they were not subject to predation, they would breed more slowly. The predators themselves, by creating aneed for more rapid multiplication, are responsible for the productionof the individuals that they slaughter. If predation had never arisen,”

“Predators would not be necessary to prevent overpopulation. Predation,including its subtle form, parasitism, is a tragic miscarriage of evolution.It is responsible for some of the worst passions that afflict that longterm predator, man, and through them for a large share of the evilsfrom which we suffer.*————————————————————————————*I write in full awareness of the influence that the predatory habit inall its manifold forms, itself a product of evolution, has had uponsubsequent evolution, speeding it up and increasing the diversity ofliving creatures, many of which are far from admirable. However,predation is only one of many selective agents, some of which, evenif acting more slowly, might have had more benign effects. I like tothink that on other planets, revolving around distant stars, gentler methods have brought life to fulfillment,and I would love to see the results.”

From A. F. Skutch, “A Naturalist in Costa Rica”

Predation and Parasitism

Predation and Parasitism

Adaptive Geometry of a Selfish Herd(W. D. Hamilton)

“Adaptive Geometry of a Selfish Herd”

400 Frames per second (3/100ths of a second)

Thomas Frazzetta

C. S. Holling

C. S. Holling

Gause’s Predator-Prey Experiments

Georgi F. Gause

Gause’s Predator-Prey Experiments

Georgi F. Gause

Gause’s Predator-Prey Experiments

Georgi F. Gause

Industrial Melanism Numbers of Typical and Melanic Marked Moths (Biston betularia) Released and Recaptured in a Polluted Woods Near Birmingham and an Unpolluted Woods Near Dorset*__________________________________________________________

Polluted Woods Unpolluted Woods__________________________________________________________ Numbers of marked moths released

Typical 64 496Melanic 154 473

Number of moths recaptured

Typical 16 (25%) 62 (12.5%)Melanic 82 (53%) 30 (6.3%)

__________________________________________________________ * The wild population in the polluted woods was 87% melanic. Source: From data of Kettlewell (1956).

Lotka-Volterra Predation Equations

coefficients of predation, p1 and p2

dN1 /dt = r1 N1 – p1 N1 N2

dN2 /dt = p2 N1 N2 – d2 N2

No self damping (no density dependence)

dN1 /dt = 0 when r1 = p1 N2 or N2 = r1 / p1

dN2 /dt = 0 when p2 N1 = d2 or N1 = d2 / p2

Alfred J. Lotka Vito Volterra

“NeutralStability”

Functional response = rate at which Individual predators capture and eat more prey per unit time as prey density increases C. S. Holling

Numerical response = increased prey density raises the predator’spopulation size and a greater number of predators consume An increased number of prey

Mike Rosenzweig

Robert MacArthur

Mike Rosenzweig

Robert MacArthur

Moderately efficient predatorNeutral stability — Vectors form a closed ellipse. Amplitude of oscillations remains constant.

<—Mike Rosenzweig Robert MacArthur —>

Unstable — extremely efficient predatorVectors spiral outwards until a Limit Cycle is reached

Mike Rosenzweig

Robert MacArthur —>

Damped Oscillations — inefficient predatorVectors spiral inwards to stable equilibrium point

Mike RosenzweigRobert MacArthur —>

“Prudent” Predation and Optimal Yield

Feeding territories

Consequence of senescence

Predator Escape TacticsAspect DiversityCryptic coloration (countershading)Disruptive colorationFlash colorationEyespots, head mimicryWarning (aposematic) coloration Alarm signalsHawk alarm callsSelfish callersPlant secondary chemicals

Head Mimicry Papilio caterpillar Pit Viper caterpillar DeVries Snake head

Selfish caller Hypotheses

1. Full up “I see you”

2. Mass pandemonium

3. Keep on moving

4. Mixed species flocks, fake alarm calls

<— Oogpister - Heliobolus lugubris