Chapter 16 - Long-Term Change

Notes for Chapter 16 (in part to p. 389):
Long-Term Change in Communities

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Case History: The Suez Canal

         Featured localities:
          Mediterranean Sea
                 More Links: 1 - 2 - 3 - 4 - 5 - 6
          Suez Canal
                 More Links: 1 - 2 - 3 - 4 - 5 - 6 - 7
         Red Sea
                 More Links: 1 - 2 - 3 - 4 - 5 - 6

RQ 16.1: When was the Suez Canal passageway between
the Red Sea and the Mediterranean Sea sufficiently opened
to permit organisms to move between these seas? What
trends have been observed since then?

I. Long Distance Dispersal
terms: exotic species

a) The Role of Ships in Transporting Exotic Species

b) Chances of Survival of Invading Species

c) Three Case Histories: Oysters, Lobsters, and Worms
terms: indigenous species

         Featured Organsims:
        Crassostrea gigas (Pacific oyster, exotic species native to Japan,
                intentionally introduced on the West Coast and elsewhere)
        Ostrea lurida (Olympia oyster, indigenous species native to
                Puget Sound, now relatively rare)
        Homarus americanus (American lobster)
                More Links: 1 - 2 - 3 - 4 - 5 - 6
        Nereis diversicolor (European polychaete "ragworm")

RQ 16.2: Contrast the oyster, lobster, and worm examples above
with respect to the success of intentional introductions of exotic
species.

d) The Effects of Exotic Species on Indigenous Communities
terms: endemic species

II. The Evolutionary Increase of Marine Species
terms: Sepkoski's marine fauna's: Cambrian fauna,
Paleozoic fauna, Modern fauna

a) New Species, New Ecological Abilities

RQ 16.3: Judging from the fossil record of animal life, in what
ways does the "Modern" fauna of Sepkoski's comparisons of
marine families of organisms through time differ from earlier
faunas such as the "Paleozoic" or "Cambrian" faunas?

b) The Rise of Spartina townsendii

         Featured Organsim:
              Spartina townsendii is a new species of cordgrass,
                    which formed through hybridization in about
                    1870 in England. Hybridization in this case
                    involved the combining of genetic material
                    from two parental species, Spartina alternifolia
                    from N. America, and its indigenous relative,
                  Spartina stricta. Spartina has also recently
                  invaded the West Coast, along with many
                    other exotic species with potentially serious
                    consequences such as the green crab (see
                  Cancer links below).

RQ 16.4: In what way is the case of Spartina townsendii
quite unusual among examples of new species being added
to a community? How does its addition affect the nature
of the community it has become part of?

    c) Biogeographic Clues to Past Evolutionary Modifications
        of Communities

         Featured Organsims:
               Cancer crabs (Cancer spp.)
                More Links: 1 - 2 - 3 - 4 - 5 - 6 - 7
               Sea snakes (Hydrophiidae)
                More Links: 1 - 2 - 3 - 4 - 5 - 6 - 7

RQ 16.5: Contrast the western and eastern Pacific faunas
in the northern hemisphere (e.g., Japan vs. California or
Tahiti vs. Panama), using the examples of the crab genus,
Cancer, and the sea snake family, Hydrophiidae, to
illustrate trends that have been observed.

III. The Long-Term Effects of Climatic Change

a) Giant-Scale Exterminations by Ice-Age Cooling

RQ 16.6 (Figs. 16.9 and 16.10): Contrast the impact of the
most recent Ice Age on the Pacific and Atlantic Oceans.
How did the impact on these oceans differ and how can
these differences be best explained?

b) Subtle Shifts in Community Composition Due to Sea
Surface Warming

RQ 16.7: How did the slight 0.5°C increase in seawater
temperature around the British Isles, between 1925 and 1962,
affect the communities of marine organisms that were found there?

    c) Effects of Warmer Waters: Adjustment of Competitive
        Abilities, Alteration of Ecosystem Timetables, and
        Extermination of Species (not covered)

d) Long-Term Weather Cycles (not covered)

IV. Mathematical Models of Ecosystem Dynamics and
Change (not covered)

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