Densitydependent something that depends on the amount of organisms in a unit area 5 examples to follow So what in the world is a densitydependent limiting factor Crowded populations mean the individuals have to compete for food water space sunlight or anything else necessary for ID: 650650
Download Presentation The PPT/PDF document "Density-Dependent Limiting Factors" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Density-Dependent
Limiting FactorsSlide2
Density-dependent:
something that depends on the amount of organisms in a unit area. (5 examples to follow)
So what in the world is a density-dependent limiting factor??Slide3
Crowded populations mean the individuals have to compete for food, water, space, sunlight, or anything else necessary for survival and reproduction
Some may have enough to survive, but can’t raise offspringSome may die of starvationThe more individuals in an area, the faster resources are used up
Could be between individuals of the same or different species
CompetitionSlide4
Predator-prey relationships tend to fluctuate (go up and down)
If there is a lot of prey, the predator can eat more, increasing the number of predatorsIf the prey decreases too much in population, there won’t be enough food for predators and so the population of predators decreases
PredationSlide5
Plant and herbivore populations fluctuate just like the predator and prey populations
Herbivory
(Predation of Plants)Slide6
Parasites and disease causing organisms feed at the expense of the host
This can weaken or kill the hostThe larger the population the easier it is for the parasite or disease to travel through hosts
Parasitism and DiseaseSlide7
Some species will fight amongst each other if they are overcrowded
This fighting can cause stress leaving individuals susceptible to diseaseIn a few species, overcrowding can cause females to neglect or kill their own offspring
Stress from OvercrowdingSlide8
Density-Independent Limiting FactorsSlide9
A factor that affects all populations in similar ways, no matter the population size or density
It includes things like:HurricanesDroughts
Floods
Natural Disasters
So what is it?Slide10
So what would happen after a drought?
No water so species will compete for the waterWAIT A SECOND MR. BLAUVELT! YOU’VE TRICKED US!
Wait a second…is it really density dependent?Slide11
Sometimes a density independent factor can lead to a density dependent limiting factor like competition
What do you think??Slide12
We said that something happens to stop populations from growing.
How do density-independent and dependent factors play into this?Thinking back to logistic growth…Slide13
These limiting factors contribute to what is called carrying capacity
Defined as: the maximum number of individuals of a species an environment can support
Carrying CapacitySlide14
On a graph…Slide15
On a sheet of paper, write a paragraph explaining whether or not you think that density independent factors should be considered separate from density dependent factors.
Explain your answer using information from today.
Exit Ticket