Bio test
What are the four things that biologists need to know in order to predict the future demographics of a population?
1. How many individuals of each age are currently alive 2. How many offspring females of each age reproduce 3. How many individuals of each age survive 4. How many individuals of each age immigrate and emigrate
which zone cannot support photosynthetic organisms
aphotic zone
background extinctions occur
because species are poorly adapted
not a hypothesis of the Cambrian explosion
reduction of genes that control the body layouts
What is parsimony?
simplest explanation is likely correct
dispersion pattern= spacing between individuals
true
life tables are often used to follow a cohort
true
Suppose researchers marked 800 turtles and later were able to trap a total of 300 individuals in that population, of which 150 were marked. What is the estimate for total population size?
1600
how many patterns of dispersal are there?
3
Approximately how far back in time does the fossil record extend?
3.5 billion years
how many different levels of ecological study are there?
5
Using the mark-recapture method you initially marked 25 unicorns. After a few months, you come back to the same place and recapture a total of 30 unicorns, 10 of which had been marked by you previously. How many unicorns can you calculate are in the total population?
75
Define the term biome and list the most important abiotic factors that determine what species live in particular terrestrial and aquatic biomes
A biome is a set of abiotic (nonliving) factors that determine the suitability of an environment for particular species. The most important abiotic factors that determine what species live in particular terrestrial environments are temperature and moisture. The most important abiotic factors that determine what species live in particular aquatic biomes are salinity, water depth, nutrient availability, and water movement.
Explain how the mark and recapture method of population estimation is used?
A portion of the population is captured, marked, and released. Later, another portion is captured and the number of marked individuals within the sample is counted. Since the number of marked individuals within the second sample should be proportional to the number of marked individuals in the whole population, an estimate of the total population size can be obtained by dividing the number of initially marked individuals by the proportion of marked individuals in the second sample.
Explain adaptive radiation and the one of the two causes.
Adaptive radiations is when a lineage rapidly produces many decedent species with a wide range of adaptive forms. This adds many branches to the tree of life. Adaptive radiation can be caused by ecological opportunity. This is the availability of more resources or new type of resources. For example colonizing a new area with few competitors or predators.
What is an ecosystem and what is ecosystem ecology the study of?
All living things in an area plus nonliving components of the area (air, water, nonliving components in soil). It is the study of how nutrients and energy move among organisms and through the surrounding atmosphere, soil and/or water.
What does a s shaped population curve mean?
An s shaped population curve means that the population has reached its carrying capacity and the deaths have equaled the births.
For many years, scientists believed that almost all animal lineages burst into being during the Cambrian era (just after the end of the Precambrian super eon). However, there have been many recent findings of animal-like fossils and "trace fossils" (fossils of an animal-like organism's movement) from the late Precambrian. Which of the following best explains why it took so long to realize there was animal-like life in the Precambrian?
Animals from the late Precambrian had soft bodies.
It is important for aquatic areas to turnover either due to upwelling or seasonal changes because nutrients needed for survival are found in the ____ layer.
Aphotic
Explain the difference between background extinction and mass extinctions
Background extinctions- Are occurring all the time, occurs when normal environmental changes, emerging disease, predation pressure, or competition with other species reduces certain populations to zero. Mass extinctions- Results from extraordinary, sudden, and temporary changes in the environment. Occur due to exposure to exceptionally harsh, short term conditions regardless of adaptation.
Explain how two locations, both equidistant from the equator, can have completely different climates and biomes.
Climate is based on both temperature and rainfall. While an equal distance from the equator might determine temperature, it has no impact on the amount of rainfall an area may receive. Lack of, or a deluge of, rainfall greatly impacts the vegetation and other species that live in the area. Biomes can vary greatly from the Sahara Desert to the tropical rainforests of Southeast Asia while both being located on the same latitude.
Briefly explain the difference between density and dispersion.
Density is how many individuals are in a certain area. Dispersion is how those individuals are arranged (clumped, uniform, or random).
Explain how the water moves nutrients in a lake
During the spring water warms to 4°C and sinks to the lake bottom During the fall water cools to 4°C and sinks to the bottom
What is exponential growth?
Exponential growth applies in situations with no environmental limits on growth. It is mainly at early stages of establishing a new population (before environmental factors are limiting). In terms of growth, bigger N= faster growth.
How do fossils form?
Fossils form by fossilization which is a rare event, because it requires fast burial and slow decay which is opposite of normal scenarios
explain what global ecology focuses on, and what it studies.
Global ecology mainly focuses on the biosphere where all life exists. What global ecology studies is how humans are modifying the land and releasing large amounts of chemicals to the biosphere hurting ecosystems.
Why do we use math to model population growth?
In real life, population growth is complex & we may not know all the factors at play. We use mathematical graphs and structures to represent real world situations.
The fossil record is not a perfect representation of life on Earth because it's biased for
It is biased for habitats that favor fossil formation, organisms with hard parts, recent organisms over ancient organisms, and abundant organisms over rare organisms.
Why is it important to look at population growth through mathematical models?
It is important to look at population growth through mathematical models because they simplify processes that are complex and involve many factors. Mathematical models help compare expected values and observed values. When the expected and observed values do not match up, it means there was a factor(s) not accounted for. Finally, mathematical models can be used to make mathematical predictions about the future, based on the mathematical interactions previously found throughout the population. That is why it is important to look at population growth through mathematical models.
What is the definition of thermocline?
It's the boundary between warmer upper water and cold deep water, mostly seen in oceans and lakes.
How do mass extinctions differ from background extinctions?
Mass extinctions cause a larger proportion of organisms to go extinct than background extinctions.
How are mass extinctions helpful to biodiversity? How did this help mammals after the cretaceous extinction?
Mass extinctions leave niches open to be filled by new species. Mammals that survived were able to fill niches left after the extinction event and develop to better take advantage of the niche's resources
Can the number of different species of a biome be determined by how close it is to the equator?
No, it cannot. While places closer to the equator are generally hotter, temperature is only one factor in biodiversity. The other factor is rain, something that is not based on how close a biome is to the equator. For example, the Sahara desert is close to the equator, but has no rainfall, and therefore little diversity. The rainforests of southeast Asia, however, have lots of rainfall with the same temperature, making them very diverse.
exponential growth
Nt=N0e^rt dN -----= rN dt
Explain three methods by which nutrients enter the photic zones of water.
Nutrients can already be present in sunlight rich areas in shallow water, they can reach oceans through estuaries, where rivers & streams which come down from inland areas meet ocean, and they can be brought into the photic zone through thermocline mixing of lake layers during the spring and fall or ocean upwelling due to prevailing winds.
Give one pattern of distribution and an example of where it might be seen in nature.
One pattern of distribution is uniform distribution where organisms are found evenly dispersed, often due to territorial tendencies or marking. Penguins are an example of uniform distribution.
In aquatic environments, nutrients are abundant in the benthic zone while sunlight is abundant in the photic zone. If both are needed, how can aquatic environments be productive and biodiverse?
One solution is that the benthic and photic zone overlap each other. It is shallow, but deep enough, thus obtaining the needed nutrients and oxygen in each zone. Another reason is the mixing due to seasons. Lakes in temperate regions are stratified by temperature in the summer and winter but are mixed in the fall and spring. This brings oxygen to benthic zone and nutrients to photic zone.
Compare producers and consumers.
Primary producers (aka autotrophs) make complex molecules they require (sugars, etc.) from simple inorganic compounds found in their environment using energy from the sun, a geothermal vent, etc. Consumers (aka heterotrophs) must obtain complex molecules (sugars, etc.) and therefore also chemical energy by consuming other organic material/organisms.
What is the difference between a symplesiomorphy and synapomorphy?
Symplesiomorphy is an ancestral character shared by two or more taxa, but also with other taxa linked earlier in the clade. A synapomorphy is a characteristic present in an ancestral species and shared exclusively by its evolutionary descendants.
List the two major types of biomes and explain the conditions important in determining each.
Terrestrial and Aquatic. Terrestrial biomes conditions are determined by temperature and moisture. Aquatic biomes are determined by Salinity, water depth, nutrient availability, and water movement.
Biomes are a set of abiotic factors that determine where species can live. What are the two most important types of biomes and the abiotic factors that define them?
Terrestrial biomes is about the temperature and moisture, to where its about the climate. The aquatic biomes is about the salinity, water depth, nutrient availability, and water movement.
what are the most important abiotic factors for a terrestrial biomes and aquatic biomes?
Terrestrial biomes: Temperature & moisture (Climate) Aquatic biomes: Salinity, water depth, nutrient availability, water movement
Explain how Fossil record can be biased?
The Fossil records we have are not a good representation of the life that was around in those periods because fossils require very specific circumstances to be preserved and these favor certain species living in certain environments.
Describe the differences between the Permian extinction and the Cretaceous extinction.
The Permian extinction occurred over 250 million years ago and occurred due to massive volcanic eruptions that spewed more than 4 million km3 of lava over Siberia. This resulted in the death of more than 96% of marine species and 70% of terrestrial species. The Cretaceous extinction occurred due to an asteroid striking Earth that was around the size of Mt. Everest. This resulted in catastrophic wildfires, tsunamis, and acid rain. Between 60-80% of multicellular species died.
Describe one terrestrial biome of your choice in detail.
The boreal forest biome is the biome located between the temperate deciduous forest and the tundra. It is in northern regions of the planet, but not too far north so that trees cannot grow. The average rainfall is lower than that of deciduous forests, but slightly higher than the tundra. Overall, average rainfall is low with low variation and average temperature is also low, but with very high variation. Because of the poor soil quality, trees grow widely spaced apart. The vegetation is dominated by spruce, and lichen covers the ground rather than grass.
Describe the 6th mass extinction
The sixth mass extinction is being caused by us, the human race. It is happening now and has been happening since around the 1800's or the start of the industrial revolution. Since then the extinction rates of mammals, birds, vertebrates, reptiles, amphibians, and fish have all drastically increased. The sixth mass extinction has been caused by habitat loss, global warming, and the introduction of new invasive species.
Name the two models of population growth and explain the difference between them.
The two models of population growth are exponential growth and logistic growth. Exponential growth displays population growth of a species to its full potential. It applies in hypothetical situations or in early stages of establishing a new population when there are no environmental limits on growth. Logistic growth displays population growth of a species when environmental limits are taken into account, and the population reaches carrying capacity.
Explain what dispersion patterns are and how they are different from one another.
There are three main dispersion patterns that are as follows from most common to least common clumped, uniform, and random. The difference of these three patters is that clumping is aggregate in patches, uniform is evenly dispersed, and random is spacing independent and unpredictable.
Explain how to determine the abundance of an immobile versus a mobile species.
To determine the abundance of an immobile species, you simply have to count a random sample of area in the habitat and extrapolate the data. For a mobile species, you have to use the mark-recapture method. This is when at time 1, a selection of individuals is captured, marked, and then released. At time 2, another selection of individuals is captured again and the amount that are marked are counted. The formula for this method is M/N = m/n where M is the initial number of the population marked, N is the total population size, m is the number marked that were recaptured, and n is the total number recaptured. From this equation, the total population size can be determined
If a scientist wanted to predict future demographics of a population, what do he/she need to know in order to do this?
To figure out future demographics of a population, you first need to know how many people of each age are alive. Then you need to know how many offspring females of each age produce, how many individuals of each age survive, and how many individuals of each age immigrate and emigrate
What is a trophic web? Explain what are producers and consumers are
Trophic" in ecology means to do with food. The Trophic web is a food web. The arrows show how direction of energy movement, prey to predator. Primary producers or autotrophs make complex molecules they require from simple inorganic compounds found in their environment using energy from the sun, a geothermal vent, etc. Producers bring energy into the ecosystem in a form usable to consumers. Consumers or heterotrophs must obtain complex molecules and therefore also chemical energy by consuming other organic material/organisms. Survival of consumers ultimately relies on producers.
both rainforests and deserts have the same temperatures and climates, but rainforests have a higher biodiversity, how can this happen?
Tropical rainforests have an increased rainfall when compared to desserts that get minimal to no rain at all. Because of this trees and plants can grow in rainforest locations and proved a biome that can support a larger population or organisms than a desert can. Sometimes it doesn't just depend on the temperature of a place it also depends on how much water it reserves
briefly explain how energy and nutrients are often separated in aquatic environments and the ways in which the two are brought together and allow life to flourish in certain aquatic biomes.
Ultimately nutrients are recycled into the environment when organisms die and decay or are eaten by others. In aquatic environments that means that nutrients are abundant in the benthic zone, but sunlight is abundant in the photic zone. Since both nutrients and sunlight are needed for productivity one solution includes some aquatic environments in which the benthic and photic zones overlap. Another solution is mixing during season such as lakes in temperate regions that are stratified in the summer and winter but are mixed in the fall and spring, bringing oxygen to the benthic zones and nutrients to the photic zone. Other solutions include mixing because of currents as well as receiving nutrients from inland.
Where do nutrients come from?
Ultimately, nutrients are recycled into the environment when organisms die and decay/are eaten by other organisms.
What is still lacking in the hypothesis of an asteroid impact as the cause of the end-Cretaceous mass extinction?
a complete explanation of why some lineages surveyed while others vanished
cohort
a group of individuals of the same age from birth to death
a biome is
a set of abiotic factors that determine the suitability of an environment for particular species
Explain the difference between an anthrome and a biome
a. Anthrome i. Globally significant ecological patterns created by sustained interactions between humans and ecosystems b. Biome i. Community of flora, fauna, and bacteria occupying a major habitat
Whatever its ultimate cause(s), the Cambrian explosion is a prime example of ________.
adaptive radiation
what term is when a single lineage rapidly produces any descendant species with a wide range of adaptation
adaptive radiations
in a demography life table, which of the following are included
age class, survivorship, numbest of survivors
what is not a characteristic of a population
amount of resources
the specific abiotic factors defining a terrestrial biome
annual variation in temperate and precipitation and average annual temperature and moisture levels
which marine zone would have the lowest rates of primary productivity
aphotic
the ocean sea floor is called
benthic zone
.. can be defines as a thin zone surrounding the earth where all life exists, the sum of all terrestrial and aquatic ecosystems
biosphere
demography is determined by
birth, death, immigration, emigration
what is not a level of ecological study
clade
Some beetles and flies have antler-like structures on their heads, much like male deer do. The existence of antlers in beetle, fly, and deer species with strong male—male competition is an example of
convergent evolution
Which mass extinction was responsible for wiping out most dinosaur lineages?
cretaceous
logistic growth when N is small
dN -----= rN dT
Logistic growth
dN -----= rN(K-N dt ---- K)
what term is the study of the vital stats of population and how they change over time
demography
An ecologist recorded 12 white-tailed deer, Odocoileus virginianus, per square kilometer in one woodlot and 20 per square kilometer in another woodlot. What was the ecologist comparing?
density
What are the two causes of adaptive radiation?
ecological opportunity and evolution of a key, innovative trait.
which level of ecological study focuses the most on abiotic factors
ecosystem ecology
ecological organization arranged from most to least inclusive
ecosystem, community, population, organism
estuary is the name given to any part of the ocean where life cannot survive
false
metapopulations are groups of different species in the same geographic location
false
one common and easy and important part of showing population growth of a population is by making a model
false
primary producers, heterotrophs, make complex molecules using inorganic compounds in the environment and engird for the sun
false
the aphotic zone is from o to about 200m down
false
the logistic growth graph would look like a J shape and wouldn't have a carrying capacity to it
false
the pelagic zone is the sea floor and the benthic zone is the water above it
false
the range of a population does not change over time
false
the thermocline is a measure of the salinity of a body of water over depth
false
the value of K is always changing as the death and birth rates change
false
trophic web is the breakdown of water depth influences on sunlight availability
false
what causes a clumping dispersion pattern
family groups and an abundance of resources in the area
Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception.
genetic drift
a hallmark for adaptive radiation
higher oxygen levels
a shared trait between 2 species based on a common ancestor is
homologous trait
organismal ecology
individual organisms. study of adaptations that allow individuals to live in a particular area
which is likely a biotic facto limiting songbird distribution in Hawaii to alpine habitats
insects causing fatal diseases in songbirds at lower altitudes
what is not one of the five mass extinctions
jurassic
Anole lizards underwent adaptive radiation on the Carribean islands. They show all of the hallmarks of adaptive radiation. These include all of the following EXCEPT...
lack of predators
What are anthromes?
land that shows direct alteration by humans by things such as farming, logging, grazing, etc.
salinity
ocean water is 3% salt and covers 75%
what are the 5 types of ecological studies
organismal, community, global, ecosystem, population
Most organisms are well-adapted to a particular range of conditions. What is a fitness trade off of the different concentrations of salinity?
organisms cannot survive in a different range salinity conditions
there part of the ocean not near the shore or near the bottom of the deep ocean also known as the open ocean zone
pelagic
what extinction is referred to as 'the great death' killing 96% of marine life and 70% of terrestrial species
permian
what zone is the top level of the ocean
photic zone
the number of individuals per unit area is known
population density
what is an important biotic factor that can affect the structure and organization of biological communities?
predation, competition
Which of the following groups would be most likely to exhibit uniform dispersion?
red squirrels, which active defend territories
what abiotic factors determine species distribution and abundance in aquatic biomes
salinity, water depth, nutrient availability
Which statement represents the best explanation for the observation that the nuclear DNA of wolves and domestic dogs has a very high degree of sequence homology? Dogs and wolves
share a very recent common ancestor
what are the following characteristics of a population
size, distributions and dispersion, demographics, growth
what is not a hallmark of adaptive radiation
slow allele frequency changes
carry capacity is not determined by
species diversity
global ecology
study of how humans are modifying landscapes and releasing massive amounts of energy and nutrients to the biosphere, causing changes that transcend individual ecosystems.
ecosystem ecology
study of how nutrients and energy move among organisms and through the surrounding atmosphere, soil and/ or water
population ecology
study of how the distribution and abundance of individuals in a population change over time
one of the most important abiotic factors for terrestrial biomes is
temperature
what best describes the effect of climate on terrestrial bile distribution?
the average climate and pattern of climate are important in determining bio distribution
methodical modeling is
the process of using mathematical structures to represent real world situations
community ecology
the study of nature and consequences of the interactions between species
what is demography
the study of the vital stats and how they change over time
biotic potential per capita growth rate of a population under the ideal environmental conditions
true
consumers transfer inorganic molecules into the organic complex molecules and introduce them into the food webs
true
estuaries are very abundant in nutrients and sunlight making them one of the most productive environments on earth, but they are not isolated. estuaries are where flowing freshwater meets the sea
true
if no limits are placed on a population it will experience exponential growth
true
lakes in temperate regions are stratified by temperature in summer & winter but are mixed in fall &spring, bringing in oxygen to benthic zone & nutrients t photic zone
true
most of the nutrients in the ocean are in the benthic zone
true
population ecology is the study of how the distribution and abundance of individuals change over time
true
red wavelengths are required for photosynthesis
true
the vast majority of photosynthesis occurs in the oceanic photic zone
true
there can be many populations within the range of a species
true
water depth influences the sunlight availability
true
what is not a factor that limits the distribution and abundance of species?
water evaporation rate
the factors that determine species distribution and abundance in aquatic biomes are salinity, water depth, nutrient availability and
water movement
what cane said about aquatic environments
water selectively reflects and absorbed certain wavelengths of light
What does a climograph show
what average annual temperatures and rainfall are