Download 512-526 Extinction of Mammal Populations in Western North

Figure 6.16
Hawaiian honeycreepers – the original finch (now extinct) probably ate insects and nectar
cnx.org Concepts in Biology
APES
Community Interactions
Anole lizard with dewlap extended
Cheetah scent-marks a tree
Chipping sparrow with nest of young
Flatworms in mountain streams of Britain
Monarch butterfly collects nectar from flower
Garden spider with web catch
Dwarf mistletoe on a conifer
Population variation in northern Canada
APES
TERRESTRIAL ECOLOGICAL SUCCESSION
(Botkin and Keller. 2011. Environmental Science)
Gradual change in the assemblage of
organisms (community) following an
ecological disturbance.
Early small plants and trees contribute
to early peak in biomass and
diversity. Decline as larger shade
trees grow abundant. Some species
colonize and become numerous, some
species decline in population. All
species not in “climax state” (peak) at
same time. Over time, succession
leads to “mature community”.
In the mature community, small to
moderate ecological disturbances
(storm, fire, dead tree falling, etc)
open up small patches to early
successional species.
Result is mature community with
various states of succession in patches
= high biodiversity.
Common elements in any succession - “successional stages”
Early
early vegetation, small
size, adapted to bright
light, unstable conditions
Middle
vegetation rapidly
growing, rapidly
spreading seeds
Late
large plants/trees dominate, slower
growing, longer lived, seeds not
widely dispersing, smaller plants
adapted to shade
An event caused by physical, chemical, or biological agents that results in changes in
population size or community composition is a disturbance. Natural ecosystem disturbances
include hurricanes, ice storms, tsunamis, tornadoes, volcanic eruptions, and forest fires.
Note to students: Please browse the U.N. Millennium Ecosystem Assessment to view the
summary of findings about the effect of human disturbance on global ecosystems.
Lake Succession
A series of changes
(primarily increased
sedimentation and vegetation)
In which a lake progresses from
oligotrophic
to
mesotrophic
to
eutrophic
to
terrestrial
Extinction of Mammal
Populations in Western North
American National Parks
Newmark WD. 1995. Conservation Biology. 9(3): 512-526
Bryce Canyon
Crater Lake
Glacier-Waterton Lakes
Grand Canyon
Kootenay-Banff-Jasper-Yoho
Lassen Volcanic
Manning Provincial
Mount Rainier
Olympic
Rocky Mountain
Sequoia-Kings Canyon
Yellowstone-Grand Teton
Yosemite
Zion
Extinction of Mammal Populations in Western North American National Parks