Island Biogeography
Mangrove islands off the Florida coast
Mangrove Island Close-Up
Dan Simberloff on Mandolin Nick Gotelli on Guitar
Simberloff’s defaunation experiment on Mangroves
Results from Simberloff’s Experiment
Results from Simberloff’s Experiment pt. 2
Island Effect Why are there fewer species on islands than on equal sized areas of mainland? Differences purely to area? Differences due to mainland having more complex habitat?
Bracken Fern
Bracken Fern - Australia
Number of species found on Bracken Fern
Picture Winged Drosophila
Picture Winged Drosophila – more than 500 species from 1 ancestor
r_YhATOYA&list=PL6C F1C81 &index=6http:// r_YhATOYA&list=PL6C F1C81 &index=6
Cichlid Diversity
African Rift Lakes
Cichlids from Lake Tanganyika (left) and Lake Malawi (right)
Age of African Rift Lakes Lake Tanganyika – 12 million years old; about 250 species of cichlids; 80% endemic Lake Malawi – 5 million years old; about 700 species of cichlids; again 80% endemic Lake Victoria – 250,000 to 750,000 years old; about 400 species of cichlids – over 80% endemic
The dodo What makes species vulnerable to extinction?
What makes some populations or species vulnerable to extinction?
Rare species are more vulnerable to extinction Remember Rabinowitz – three factors determine rarity: 1.Geographic range 2.Width of habitat use 3.Local population size
Passenger pigeon
Passenger pigeon
Allee Effect Some species have a minimum requirement for population size in order to successfully breed
Characteristics that predispose species to becoming extinct 1. habitat overlap - the species occupy habitat that is desirable to humans and lose out in competition with humans for the habitat - tallgrass prairie species 2. human attention - species suffer because singled out by humans - either desired as food or fur and hunted heavily (passenger pigeon, dodo, northern elephant seal); or disliked by humans and killed as varmints (wolves, African wild dogs) 3. large home range requirements - animals needing large areas can’t find large enough areas in human dominated landscape - California condor, polar bear 4. limited adaptability and resilience - salmon return to natal stream to reproduce; won’t go elsewhere
Habitat overlap – Konza Prairie, Kansas
Human attention – African wild dog
Large Home Range Requirements - California Condor
Limited adaptability and resilience - Coho salmon
Salmon Life Cycle
Coho Salmon support 137 species
Additional factors Species in which population size is declining Animal species with large bodies Species that are not effective dispersers Seasonal migrants Species with little genetic variability Species with specialized niche requirements Species usually found in stable, pristine environments Species that form permanent or temporary aggregations Species that have not had previous contact with people Species closely related to other species that have gone extinct or that are endangered
Species in population decline – barn owls
Species with large home ranges – Polar bear
Animals with large bodies
Species that are not effective dispersers - Freshwater Mussels
Seasonal migrants such as Blackpoll Warbler
Species with little genetic variability – Madagascar fish eagle
Species with specialized niche requirements – hummingbird flower mites
Species usually found in stable, pristine environments
Species that form permanent or temporary aggregations
Species with little or no prior contact with people – Western Australia flora
Species related to other extinct or endangered species - Cranes
Worldwide Endangered Species
Endangered tree species - worldwide
Rare and Endangered Species in Japan
Endangered species in Canada and the US – as of 1990’s
Threatened and Endangered Species
Threatened And Endangered Species in Illinois
Four-toed salamander – found at Green Oaks
Past Climate Change
Coring Glacial Ice
Ice Core Data
Pollen core data collection
Pollen Core Data
Distribution of North American Trees in past 16,000 years
Black-tailed prairie dog
Northern bog lemming
Eastern chipmunk
Global Ice Coverage Last Ice Age
Rainforests in: a. Glacial period, b. Inter-glacial period
Global carbon cycle
Carbon dioxide concentration at Mauna Loa
Change in Average Global Temperature
Statistics and climate change yer_embedded&v=e0vj-0imOLwhttp:// yer_embedded&v=e0vj-0imOLw
Surface temperature trends from eo/2011/oct/20/berkeley-earth-climate- change-videohttp:// eo/2011/oct/20/berkeley-earth-climate- change-video
Model predictions of global temperature increase
Predicted surface change
Current distributions of biomes
Predictions for biomes after global warming
The Earth Ice Free
Global Ice Coverage Last Ice Age
Will species be able to survive current climate change? Maybe Maybe not
New Complications with Climate Change 1.Current species and populations may already be stressed by habitat loss and environmental degradation 2.Habitat loss will make it harder for species to migrate to new areas 3.Global temperature may increase to temperatures that are much greater than species experienced in the past 4.Rate of global climate change is probably faster than in geologic past
Pikas may run out of mountaintop