Lecture 37- Ecology Flashcards
What is ecology?
The study of the interaction of organisms with each other and environment.
These interactions determine
-Where they live (Distribution)
-Why they live their (Habitat) favorable conditions such as nutrients
-How do they adapt to the habitat (Adaptation)
-How many there are (Abundance)
True/False
Most organisms function singly
False- they function as a group thst interacts with the environment (population)
What can the environment affect?
The growth, survival, and reproduction of plants and animals
Environmental factors are split into what 2 main groups?
Biotic and Abiotic factors
Living and non living
Where is the richness of the biosphere most apparent?
Tropical rainforests such as the Panamanian forest
How many species approx are undiscovered?
5-30 million
What is one of the main factors that affect the biosphere richness?
Humans
How do humans affect the richness and diversity of the biosphere?
The more humans there are in a habitat, the LESS richness the LESS diversity there is
What is considered ecological time
And evolutionary time?
Ecological time is (minutes, months. Years) Evolutionary time (decades, centuries, Millennia)
Hawks eating mice have an immediate impact on prey by killing the mice.
This effects the ecology by x
It also effects the evolution by decreasing y
It affect ecology by decreasing the population of prey
Also effects evolution by decreasing the gene pool (long term effect)
What are the subfields of ecology?
Organismal ecology- deals with the disciplines, physiology, and behavior of an organism to meet the challenges posed by the environment.
Population ecology- deals with the factors that affect how many individuals of a particular species live in an area
Communist ecology-deals with the wide array of different species interacting in a community
Ecosystem ecology- deals with a community, or several, of all populations and their abiotic environment, such as sunlight. Focuses on Energy flow and chemical cycling among various biotic and abiotic components
Biosphere ecology- GLOBAL ecosystems.
Sum of ALL planet’s ecosystems.
What environmental factors affect the reproductive rate of deer mice in a field?
This q is referring to which subfieldcof Ecology?
Population ecology
What factors control the photosynthetic productivity in a temperate grassland ecosystem?
Which subfield of ecology is this referring to?
Ecosystem ecology
What factors influence the diversity of species that make up a particular forest or lake?
What subfield of ecology is this referring to?
Communist ecology
How does change in atmospheric CO2 conc affects Earth’s climate and life?
What subfield of ecology is This referring to?
Biosphere ecology
What type of distribution do wolves exist in?
Clumped
They live in groups and families to increase effectiveness of hunting, spreading work, etc
(Most common form of distribution)
What type of distribution do dandelions exist as?
Random- they get blown by seeds randomly and later germinate
What type of distribution do penguins exist as?
Uniform-as they posess aggressive interactions and prefer to be spaced out
What type of factors are called density-dependent factors and why?
Biotic factors
As the density of 1 population can change the density of another
How does competition affect population density?
- (negative for both species)
How does predation affect population density?
+ -
Positive for the predator, negative for the prey
How does parasitism affect population density?
+ -
Increases the abundance of the parasite, decreases the abundance of the host
How do commensals affect the population density?
+ 0
Benefits the commensals, host unaffected
How does mutualism affect population distribution?
+ +
Abundance of both species increases
Eg; bees and plants
Gives examples of abiotic factors and how they affect the distribution of organisms?
Temp- important factor in the distribution of organisms because of the affect on biological processes
Most cells exist 0-45C (below 0 cells rupture, above 45 enzymes denature)
Water- important factor reflecting distributions of populations. Aquatic populations are adapted to either fresh or salty water by osmoregulation
Sunlight- provides energy thst drives nearly all ecosystems
Wind- amplifies effect on environmental temp on organisms (by contributing to heat and water loss)
Climate- combination of all factors
Macro climate (GLOBAL LEVEL)
Microclimate (community level)
Human population increased relatively slowly until around which date?
And what was the population of humans at that time?
1660- with a population of 500mil
How long did it take for the human population to double from 500 mil in 1650?
And to double again to 2 billion?
And to 4 billion?
200 years to double to 1 Billion from 1650
Then only 80 years to 2 Billion (1850-1930)
Then only 45 years to double to 4 Billion (1930-1975)
What is the current human population and what is the yearly increase (2010/2011 report)
Around 7 Billion, with 83 million increase/ year
What was the growth rate of human population in 1962? What about 2010?
- 1% in 1962
1. 2% in 2010
What does the decline in human growth rate indicate?
Human population increase is not exponential, Which assumes constant rate
What does the demographic transition tend to lead the population growth rate to?
And which prominent country has achieved that?
0%, as the birth and death rate decrease to around 0
This was reached in Sweden from 1810-1960
Why did the human population growth % dip form 2 to 1.4% km the 1960s?
Because of a famine in China
When was the plague?
Around 1300s
Population decreased by thst period
