What is Carrying Capacity?
The largest population size that a particular environment can sustain for a certain time period.
What is negative feedback?
Mechanism that counteracts or reverses changes in biological systems, aiming to ensure balance
Are population curves perfect representations of real-world examples of population growth? Explain your answer.
No, they can simplify complex biological systems and represent the main, simplified pattern. Each population in various ecosystems are impacted differently by various density-dependent and density-independent factors .
Give me an example of cooperation.
- Fish Schools
- Chimpanzee Cooperative Hunting
What resources limit carrying capacity? (list at least 2)
Food, Water, and Space
Do density-dependent factors or density-independent factors tend to push a population towards the carrying capacity?
Density-dependent factors
What is the first phase of the sigmoidal population growth curve?
Exponential
These types of relationships happen between animals or plants of the same species.
Intraspecific
What is most-likely to happen to a population if it exceeds the carrying capacity of the environment it lives in?
List at least 2 density-dependent factors
-competition for resources, transfer of pathogens or pests, predation
Why does exponential growth not continue indefinitely in natural populations?
Due to limited resources which lead to competition and death, predation, and transfer of pathogens or pests.
What are the three reasons that drive competition?
- Food
- Water
- Space
How do predator-prey relationships help maintain a population near the carrying capacity?
Predators control prey populations, and when prey populations decrease due to predation, the predator population will also increase. Consequently, the prey population will increase, also increasing the predator population. This maintains a balance, keeping both predators and prey near the carrying capacity.
Explain why there is a higher risk of pathogen or pest transfer in dense populations
Because as population density increases, there is increased contact and proximity between organisms.
In what conditions would it be possible for a population to continuously grow exponentially?
In a laboratory, with ideal conditions, where the population is given adequate nutrients and space to grow exponentially.
What are all of the roles that chimpanzees have when they are cooperating?
- "Drivers" who flush out the prey
- "Blockers" who prevent escape routes
- "Ambushers" who wait to intercept fleeing prey
- "Chasers" who actively pursue the target
What is 1 sign that a population has exceeded its carrying capacity? (other than population decreasing)
-Loss of vegetation due to overgrazing
-Loss of vegetation due to overgrazing
Why does competition for resources arise as the population increases?
Total amount of resources in the environment does not increase with increasing population size, creating competition as the resources become limited
Explain each phase of the sigmoidal population growth curve
Exponential Growth Phase – Rapid population increase due to abundant resources (food, space, nutrients)
Transitional Phase – Growth slows as competition for resources intensifies ( food shortages, lack of space). Creates an S Shape and Predation and disease start having a larger impact
Plateau Phase – Population stabilizes : Birth and death rates equalize.
Carrying capacity (K) is reached—the environment can no longer support further growth.
Competition and predation prevent expansion.population growth curve.
Give the three ways competition drives evolution ?
- Natural Selection
- Population Regulation
-Evolutionary Pressure