Class Notes (837,194)
Canada (510,160)
York University (35,409)
Biology (2,273)
BIOL 1602 (40)
Lecture

mortality rates

1 Page
60 Views
Unlock Document

Department
Biology
Course
BIOL 1602
Professor
Rebecca Jubis
Semester
Fall

Description
 In populations where mortality rates are high, individuals tend to breed earlier in life  Read example on mainland and island opossums. Pg. 500-502.  Populations have not evolved longer life spans because the power of natural selection declines with age  In summary: o Evolutionary theory of senescence hinges on the observation that the power of natural selection declines late in life o This is because most individuals die, due to predators, diseases or accidents-before reaching late in life o Two mechanisms can lead to the evolution of senescence:  Deleterious mutations whose effects occur late in life can accumulate in populations  When there are trade-offs between reproduction and maintenance, selection may favour investing in early reproduction even at the expense of maintaining cells and tissues in good repair o Evolutionary theory of senescence has been successful in explaining variation in life history among populations and species 13.3- How Many Offspring Should an Individual Produce in a Given Year?  The more offspring a parent (or pair of parents) attempts to raise at once, the less time and energy the parent can devote to caring for each one Clutch Size in Birds  Selection will favour the clutch size that produces the most surviving offspring  Any individual offspring will survive decreases with increasing clutch size  The abiliiity of the parents to feed any individual
More Less

Related notes for BIOL 1602

Log In


OR

Join OneClass

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

Sign up

Join to view


OR

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.


Submit