revised Ch52B S09

revised Ch52B S09 - Biogeography Why do we see certain...

Info iconThis preview shows pages 1–12. Sign up to view the full content.

View Full Document Right Arrow Icon
Biogeography Why do we see certain species in certain habitats only?
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Concept 52.2: Interactions between organisms and the environment limit the distribution of species Ecologists have long recognized global and regional patterns of distribution of organisms within the biosphere Biogeography is a good starting point for understanding what limits geographic distribution of species Ecologists recognize two kinds of factors that determine distribution: biotic , or living factors, and abiotic , or nonliving factors
Background image of page 2
Dispersal and Distribution Dispersal is movement of individuals away from centers of high population density or from their area of origin Dispersal contributes to global distribution of organisms
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Biogeography: Biogeography is the study of the distribution of different species of organisms around the planet. It provides a starting point for understanding the limits geographic distribution of a species. Figure 50.2 Kangaroos/km 2 > 20 10–20 5–10 1–5 0.1–1 < 0.1 Limits of distribution Climate in northern Australia is hot and wet, with seasonal drought. Red kangaroos occur in most semiarid and arid regions of the interior, where precipitation is relatively low and variable from year to year. Southeastern Australia has a wet, cool climate. Southern Australia has cool, moist winters and warm, dry summers. Tasmania
Background image of page 4
How do you study factors limiting geographic distribution? Ask a series of questions? What are some of the limitations for geographic distribution of species? Figure 50.6 Species absent because Yes No Dispersal limits distribution? Behavior limits distribution? Biotic factors (other species) limit distribution? Abiotic factors limit distribution? Yes No Yes No Area inaccessible or insufficient time Habitat selection Predation, parasitism, competition, disease Water Oxygen Salinity pH Soil nutrients, etc. Temperature Light Soil structure Fire Moisture, etc. Chemical factors Physical factors
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Dispersal and distribution
Background image of page 6
Factors involved in Dispersal and distribution of species Ecologists consider multiple factors when attempting to explain the distribution of species Natural range expansion. Species transplant or invasive species behavior And habitat selection Biotic factors Abiotic factors
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Natural Range Expansions
Background image of page 8
New areas occupied Year 1996 1989 1974 Natural Range Expansions Natural range expansions Show the influence of dispersal on distribution Cattle egret: found in Africa, Asia. Not found in Americas until 200 yrs ago. late 1800 ; fly across the Atlantic and colonize south America. Moved through C America. And seen in Florida in 1950 Figure 50.7
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Species Transplant Invasive species
Background image of page 10
factor limiting species distribution? Study organisms that are intentionally or
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 12
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 43

revised Ch52B S09 - Biogeography Why do we see certain...

This preview shows document pages 1 - 12. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online