Class Notes (810,487)
Canada (494,138)
BIOC58H3 (38)
Lecture 7

Lecture 7

9 Pages
Unlock Document

University of Toronto Scarborough
Biological Sciences
Rudy Boonstra

LECTURE 7 October 30, 2007 Biological Impact of Global Change We want to go from looking at the period of time from the last glacial maximum to the present. During the Holocene we will look at. The types of things that happened to populations and make projections that will happen because of the doubling of C02. I will go back to biology 101 to familiarize yourself to think about species moving in response to major climate change. In the case of the past it would be deglaciation and now significant warming. (Reads Wallace Broecker, Cooling the Tropics, 1995) You are working with an incredibly sensitive system when working with the atmosphere. (Reads T.S. Eliot 1888-1965) That seems fairly complicated but it summarizes nicely the Paleo climatic record to the future. You guys are the future. Ecology 101: The first thing to think about when talking about species distribution is that each is unique in terms of their requirements. The niche is the profession of the species. It is how it makes it living and who it interacts with (predators etc.) It is the totality of its life. Remember for species they are faced with all sorts of environmental parameters not just temperature and moisture. Example species 1 can live at higher moisture and higher temperature whereas species 2 can live at lower moisture and lower temperature. Example: You are a white tailed deer and they live in the Eastern Deciduous forests and they can live quite happily most of the time. If we get 1 metre of snow they are dead. You only need 5 or 10 days with really deep snow and that will kill them. They dont invade Algonquin Park because of this. It isnt the means it is the extremes. They have to get past extremes or they die. It is the extremes that are important. This illustration of a Niche can be extended to 3 variables like volume but you dont know which one is important. All together they are called a hypervolume. Together it is the fundamental niche of a species and that defines where the species can live. The niche of a species can overlap with that of another but it cant overlap totally. They cant be exact in the same niche because of the competitive exclusion principle. This says that where two species do the same thing then one will be excluded because of competition. We dont compete for oxygen but for critical items if competing seriously then one survives and the other doesnt. The other thing to think about is that this idea of tolerance ranges. Here you have the tolerance zone and again I have to emphasize the importance of life stage of an organism. We are adults and very BGYC58H3F.October,30, 2007 LECTURE 7 1
More Less

Related notes for BIOC58H3

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.