Exam 1 Flashcards
Do species exist as individuals?
No, living things exist as collections.
What is the most common estimate for how many species lives on earth?
8.7 million, excluding prokaryotes. Although it could be much more.
How many species of insects are there?
1 million
How many species of vertebrates are there?
53,000
- 25,000 fish
- 5,000 mammals
- 10,000 birds
- 8,000 reptiles
- 5,000 amphibians
Have we described most species?
No, most of what is out there remains undescribed because the process of describing species is time and demands special skills which are in short supply.
Is there a central database of species?
No!
But, an attempt to create a database of phylogenetic information is underway.
What does phylogenetic tree?
A branching tree show evolutionary relationships.
What are cryptic species?
Morphologically indistinguishable groups of animals that cannot interbreed.
Have some species been named and described more than once?
Yes!
What can we learn about extinct species?
Since most species never fossilized. Many extinct, ancient species will never be known.
Are names given to fossilized species meaningful?
No, species are classified with other species that appear to be morphologically similar, but since there is so little data, we cannot be confident of what we observe and the guesses me make from our observations.
Name an example in which we might have mis-used our fossil evidence when creating species classifications?
Allosaurus. There is only one known species of Allosaurus and there is a great deal of variation between specimens attributed to the species. In reality, the fossils we have may represent several species.
In what genus are the largest specimens are the largest dinosaur specimens often placed?
Epanterias. Some specimens placed in this genus may just be very large examples of Allosaurus bones.
What taxonomic groupings do we know best?
Birds, flowering plants, mammals, butterflies are all well-known.
What taxonomic groups are not well-known?
Most insects including chalcidoids and beetles are less well-known but are becoming better understood. Moreover, only a fraction of insects have a name and a description.
What groups of species is our understanding most limited?
Microorganisms. We are only beginning to get a sense of their true diversity.
What is the Tree of Life?
The idea that all species are descended from a single ancestor.
How do we know that all forms of life have a similar ancestor?
- Except for a few viruses, which may have undergone retrograde evolution, all forms of life on earth use DNA as genetic material.
- All forms of life share a common virtually identical genetic material
- All forms of life rely on the same biomolecules-amino acid, sugars etc.
Moreover, if other unrelated forms of life excited, they have gone extinct.
What replaces the outdated animal kingdom/plant kingdom paradigm?
The Five Kingdom Scheme.
What are the five kingdoms?
- ) Protista (the single-celled eukaryotes)
- ) Fungi (fungus and related organisms)
- ) Plantae (the plants)
- ) Animalia (the animals)
- ) Monera (the prokaryotes)
What is the problem with the Five Kingdom Scheme?
It doesn’t reflect evolution very well.
Are groups that appear to be morphologically similar typically phylogenetically similar?
No! Many groups that appear to be similar are actually not very similar, at all.
What is a biological population?
Many individuals of a single species living in the same place.
What is a biological community?
Several/many populations of organisms gathered together in a given area are called a biological community.
What is alpha diversity?
div
What is gamma diversity?
Total species diversity in a given habitat.
What is beta diversity?
div
Name three areas of unexplored biodiversity?
Tropical rainforest–actually we are understanding it better as we are destroying
Ocean floor–almost totally unexplored
Microbial world–we are just scratching the surface
What percent of the earth are covered by tropical rain forests?
Yet, what proportion of the earth’s plant species are in tropical rainforests?
And, what proportion of the earth’s animal species?
Covers 6% of the earth.
4/5 of plant species
1/2 of animal species
Why are rainforests so diverse?
It is a bit of a mystery. Primary factors:
- ) History (been around for a long time)
- ) Productivity
- ) A heterogeneous environment. Biodiversity begets more biodiversity. Meaning 1 and 2 combine to produce 3.
How much of the earth does the ocean cover?
70%
How much of the air we breathe is provided bey the microscopic oxygen-producing phytoplankton floating in it?
50%
How much of the earth’s ocean is unexplored?
95%
Is the deep ocean habitable to living things?
Yes!
Does the standard species definition apply when considering the microbial world?
No, because prokaryotes, which are the majority of microbes, do not reproduce sexually. Moreover, they exchange genes in ways that don’t allow us to understand them as species in the traditional sense.
Can all microbes be cultured in a laboratory for study.
No, microbes cannot be cultures in a lab.
Do difficult environments like glaciers, deep drilled cores and hypothermal vents have biological diversity?
Yes, there has been unexpected biodiversity in all of these places.
Are ecology and evolution the same discipline?
Sort of. The mechanisms that drive evolution are ecological. And, the participants that make-up ecological interactions result from evolution.
Taken together they provide the answer to why there are so many species out there and why those species look as they do.
What is a prokaryote?
A lacks a nucleus, a mitochondria and other membrane bound organelle.
What is an autotroph?
An organism that produces its own energy typically via photosynthesis.
How does energy enter an ecosystem?
Via primary producers called autotrophs. Autotrophs create their own food via inorganic sources. Mostly, they use use solar energy to manufacture food via photosynthesis.
But, there are places such as deep sea hydrothermal vents and iron-rich rock deep below the earth’s surface where autographs use the chemical energy found in methane and hydrogen sulfide to make food.
Do primary producers create energy?
No, they use the energy available in sunlight and inorganic compounds into the chemical energy stored in sugars.
How do pollination syndromes demonstrate the interaction of evolution and ecology?
Widely divergent species of flowering plants will evolve similar pollination mechanisms or “syndromes.” Likewise, widely disparate types of pollinators will evolve to exploit these these syndromes.
What are pollination syndromes and how do they demonstrate coevolution?
A discrete set of floral, nectar, and pollen characteristics that match the sensory abilities, metabolism and biology of potential pollinators and ultimately ensure their efficient pollination by manipulating the behavior of their pollinator.
Pollinators evolve in response to these floral characteristics. This convolution then intensifies the interaction.
What is the Hawkmoth example of a coevolutionary pollination syndrome?
A flower evolves a long corolla to ensure that hawkmoth visitors must reach deeply into a flower in order to reach the nectar or the reward to the visit. By doing this the hawkmoth is then perfectly positioned to receive the flowers pollen.
Hawkmoths then evolve to longer tongues to enable them to more easily reach the flowers nectar.
This in turn places selective pressure on the flowers and intensifies the relationship.
What is the corolla?
The collective unit of petals on a flower.
What is obligate mutualism?
A type of mutualism where one species cannot survive without the other.
What is facultative mutualism?
A type of mutualism where both species can survive without the other species but both are better off if the other species is around.
What is the story of Darwin’s hawkmoth?
When Darwin saw the Madagascar Star Orchid, which has a 10 inch nectar tube, he predicted that there must be a hawkmoth with a ten inch tongue to pollinate it.
40 years later a hawkmoth with a 10 inch tongue was discovered.
What does it mean that flowers compete for pollinators?
Some flowers evolve to be more conspicuous and offer greater rewards to get more pollinators to visit the flowers, but these changes or syndromes change who can visits their flowers. Therefore restricting the scope of competition.
What happens when pollinators for through extreme ecological specialization?
They evolve to only pollinate one plant. Sometimes this protects them from interspecific competition, but sometimes it doesn’t and other pollinators maybe be able to visit “their flower”
What is interspecific competition?
When individuals of different species compete for the same resources.
What is intraspecific competition?
When individuals of the same species compete for resources.
Are all pollinators extremely ecologically specific?
No, some are generalists and able to visit a wide variety of flowers adapted to their pollination syndrome.
What is a pollination syndrome?
Flowers evolve a suite of traits to ensure they are pollinated. It can be abiotic: wind and water or biotic: bees, birds, flies etc.
What is special about the squash bee?
The squash bee feeds not the nectar of squash exclusively. Other bees can visit the squash, but the squash bee is its most effective pollinator.
Male squash bees hide in the carolla waiting for females to mate with as they forage for pollen.
The abundance of this pollinator makes it easy to grow squash and pumpkins, though most gardeners don’t know they exist.
Squash emerge in late summer.
Discuss the pollination syndrome involving most flies and bees.
Generalists: Most flies and beetles. Look for open flowers, easy to reach pollen and nectaries. Offer large amounts of pollen because that is what their visitors are after. Usually early spring.
Discuss the pollination syndrome involving long-tongued bees.
They look for moderately long corollas. White, blue yellow or infrared flowers that indicate sucrose concentrated nectar. Sometime an area to land or leaves that must be pushed apart before the nectar can be reached. They also look for scented flowers that are open in the daytime. Also, they want sticky pollen that can easily be collected and transported.
Discuss the pollination syndrome involving short-tongued bees.
White, yellow, infrared flowers short corollas with easily available pollen. Want scented flowers, open in day time. Sticky pollen. Sucrose dominated nectar.
Discuss the pollination syndrome of bumble bees.
Same as short-tongued bees but must have hang upside down and buzz to release pollen.
Discuss hawkmoth pollination syndromes.
Look for very long corollas that effectively force the moth to push its face into the stamens in order to reach the reward. Moth don’t care about the pollen so they must be tricked into transporting it. They want white heavily scented flowers that are open at night and have small amounts of concentrated nectar.
What is the stamen?
The pollen producing reproductive organ of a flower.
What is carrion?
The decaying flesh of dead animals.
What is the pollination syndrome for butterflies?
Similar to hawkmoths but they want a landing platform and they are looking for pink or lavender flowers.
What is the pollination syndrome of beeflies
Like butterflies but no landing pad.
Hummingbird polination syndrome?
Red flowers. Very long corollas with large amounts of dilute nectar. Open during the daytime. Bird is forced to push face all the way in. No scent.
Bats pollination syndrome?
Very big flowers that bats can reach their faces into. Large amounts of dusty pollen that will stick to mammal hairs. Open at night.
Carrion beetle pollination syndrome?
Flowers that smell like carrion and offer large amounts of pollen.
What is ecology?
The scientific study of the distribution and abundance of organisms, and their interactions with the environment.
What is meant by scientific study?
Different in every discipline: always uses some form of hypothesis deduction.
Process:
- ) Someone become interested in explaining how an aspect of the natural world works.
- ) Observations are made intentionally and unintentionally.
- ) A hypothesis is constructed based on those observations.
- ) Good hypothesis generate predictions that can be tested.
- ) In experimental sciences experiments are set-up in other sciences additional evidence is gathered.
- ) If prediction is not born out hypothesis is falsified.
- ) The strongest hypothesis are usually accepted if multiple experiments fail to falsify them.
- ) These hypothesis and their underlying models form scientific paradigms, which may last for centuries or long and form the basis of future scientific questions. But, they also limit it directions.
Footnote: theories cannot be proven true. They can only be proven false because any number of hypothesis can be generated to predict the same outcome.
How could the zonosemata wing markings evolve from natural selection?
Zonosemata have dark bands on their wings.
3 Hypothesis
1.) Courtship display
2.) Evolved to scare predators because it mimics a jumping spider
3.) Evolved to deter predation by jumping spiders.
Describe the experiment groups created to test the hypothesis about why Zonosemata have unique wing markings?
- ) Untreated control group
- ) Zonosemata with its own wings regaled
- ) Zonosemata with housefly wings
- ) Houseflies with zonosemata wings
- ) Untreated houseflies
How did the experimental groups developed interact with hypothesis to form predictions?
Hypothesis 1: If the wing markings evolved for sexual selection. Whether or not the zonosemata had their wings or other wings they would have been equally vulnerable to predators.
Hypothesis 2: If the wing pattern evolved to scare predators by mimicking a jumping spider then one would expect that zonosemta with their own wings would experience reduced predation from non-jumping spider predators.
Hypothesis 3: If the markings limited jumping spider predation then mortality due to jumping spider would be limited but it would not effect other predators.
Zonosemata with their own wings were killed at a lower rate by jumping spiders when they had their own wings. There was no circumstance in which their predation by non-jumping spiders was impacted.
Is ecology and historic or experimental science?
It is a historical science but it is becoming and experimental one.
What is ecologies dominant scientific paradigm?
The field is very much in flux and there isn’t one
What is a scientific paradigm?
A set of assumptions underlying a given discipline.
What levels of organization so scientist work at?
Any of the following: Individual Populations Communities Ecosystems
What is an individual?
A single discrete organism
In some cases it is easy to define. i.e. a single mouse
In other cases it is hard to define. An aspen tree might look like a single individual but under ground many aspen trees are interconnected.
A singel fungus mycelium might occupy a tens of kms underground
Give an example of a question that organismal ecology might ask?
How does a cave cricket find its way in and out of a cave each time it forages?
Examples of populations?
- ) A herd of wildabeasts
- ) All the bullhead catfish living in a midwestern lake
- ) All of the tropicbirds nesting on a single island
- ) The e.coli population of a single person’s gut.
What sorts of questions do population ecologists ask?
They ask about the abundance, density, population growth an limits to growth. For example, thy might ask how the number of available nest sites impacts the maximum number of tropicbirds and island can sustain. Moreover, the size, shape dimensions of a population not about the interactions between populations.
Talk about the different functions different species might have in a different community?
Some are decomposers; some are producers
Some species may interact a lot; some not at all.
A biological communities tightly knit systems or opportunist assemblages.
Is is not clear. It is subject of debate among ecologists.
What sorts of questions would a community ecologist ask?
Something like to what extent can parasitic wasps control outbreak of pine sawflies and therefore is the presence of parasitoids necessary for the presence of pine trees?Moreover, question about the interaction between populations.
Ecosystems
Interacting assemblages of living things in a given area. Accounting also for non-living components such as light, water, seasonality nutrients, soil. This is the difference between and community and an eco system. The study of the biologic communities doesn’t take into account the non-living elements.
Do ecosystems stand alone or are they nested within other ecosystems?
They are nested within other ecosystems.
What sorts of questions might an ecosystem ecologist ask?
The support provided by nutrients and energy brought into a bat cave via bat guano provides for non-photosynthetic ecosystems in the cave. Moreover, how living and non-living things interact.
What is a species?
No single definition. Different branches of biology use different definitions. There are three main conceptions of species:
- ) The biological species concept
- ) The morphological species concept
- ) The phylogenetic species concept
What is the Biological Species Concept?
A group of individuals who are able to interbreed and and create fertile offspring.
Great definition form an evolutionary perspective.
It is a “real” or objective concept.
It is defined by the limits of gene exchange.
What is the Morphological Species Concept?
Species are groups of organisms that share certain morphological or biochemical traits.
This definition is used by biologists for whom it is advantageous or whom cannot use the “Biological Species Concept.” For example biologists studying species that don’t reproduce sexually. Or, biologists studying fossils.
Unfortunately, this theory is very subjective.
What is the Phylogenetic Species Concept?
Species with a specific lineage, which is recognizable distinct from other such lineages.
This definition uses relationship between species to define species. And it is dependent upon the Biological Species Concept.
What is an example of how one would test hypothesis is ecology?
Two scientists (Chris Whelan and Robert Marquis) studied the role of birds in limiting the density of herbivorous insects.
-Having observed that deciduous forests harbor hundreds of species of herbivorous insects, yet only a small portion of leaves are eaten every year, they wondered if birds are an important factor in controlling herbivore insects. Especially since there are other spiders, wasps and fungal infections that would control insects.
What experiment did Whelan and Marquis create to determine the role birds in controlling herbivore insects deciduous forests?
Multiple trees are put in cages such that insects but not birds can reach them. Since the cages themselves might have an impact, control trees were also put in cages but holes were cut so that birds could access the trees.
The data collected was the percent of leaves eaten and the density of herbivorous insects.
Hypotheis: If the birds are an important agents of insect control than more leaves should have been eaten and there should be more insects in the cages without the holes.
What was the result of Whelan and Marquis’s study?
Caged trees had 70% more insects than controls and had an increased percentage of missing leaf area. Conclusion: Birds are an important potential age of herbivore control.
What are the problems of reproducibility in ecology?
In ecology, it is impossible to reproduce conditions. The conditions in a particular spot in a forest are not the same day to day let alone year to year.
What is the ecological time scales?
Ecological processes may occur over time scales ranging from days to millennia.
For example, molecules and tissues processes are completed in seconds and hours whereas populations and ecosystems are measured in centuries and millennia.
Processes ascending through time:
Biochemistry (understood through processes that occur in seconds)
Physiology (understood through processes that occur in hours weeks and sometimes years)
Ecology (months and sometimes centuries)
Evolution (centuries and millennia)
Is what we see today reflective of events that occurred centuries ago?
Yes! We are in the middle of an ecological process. For example we are in the middle of the process of forests forming after glaciation.
- Alpine tundra persist at high elevation
- Chicago was under ice 15,000 years ago “Lake Chicago” existed her thereafter, gradually growing as the glacier drained out of the Mississippi. As a result the fish here resemble the fish of the Mississippi not the atlantic.
- Deciduous trees have replaced pine and juniper trees as warm conditions persisted. In fact, a relic species of pines is still present in the Indiana dunes. Moreover, different species colonize at different rates.
What is the difference between climate and weather?
Weather is a particular set of abiotic conditions: sunlight, rainfall, temperature, humidity affecting a particular area at a particular time.
Climate, on the other-hand is the overall pattern of weather/
What is a Biome? Is it still the best way to look at vegetational areas?
A broad assemblage of plant and animal communities.
This is an old idea and it paints with very broad brush strokes.
A more recent approach is to name more specific area ecoregions.
What is an ecoregion?
They are the major ecosystems that result from predictable patterns of climate as influenced by latitude, global position and climate.
Name the 7 Biomes Molumby Focused on?
Tundra
Taiga or Coniferous Forests
Desert
Chaparral
Grasslands
--savannah
Temperate deciduous rainforests
Tropical rainforests
--Tropical dry forests.What determines the character of terrestrial biomes?
Water/sunlight/temperature/disturbance
What provides the spatial structure to biomes?
Vegetation
What creates micro-environments within biomes?
The spatial structure created by vegetation.
Describe the Tundra.
- Lack of trees
- Lichens are the dominant vegetation, along with annual grass and in some places woody shrubs and specially adapted woody plants.
- Very short growing season.
Taiga or coniferous forest?
- Cone bearing trees; usually one or a few species dominates.
- Very common–covers huge areas at high latitudes or elevations.
- The cool to warm summer are the growing season.
- In the winter it is too cold for photosynthesis and the plants are dormant.
- Precipitation often falls as snow and the ground accesses it via snow melt.
Desert?
- Low rainfall
- Many deserts are hot and dry, but some are cold most of the year (The Gobi and the Great Basin)
- The dry environment often causes a dynamic difference between the night and day temperature.
- Grasses found when there is water or is dormant as seeds
- Usually not trees/often water hoarding succulents
Chaparral
- Created by a cold ocean current moving along the side of a continent.
- About 5% of California is Chaparral
- Cool rainy winters and dry summer.
- Dense spiny evergreen shrubs
- Destined to burn in the summer. Some plants evolve to induce fire.
- High biodiversity. Lots of endemism.
Cyanobacteria
Blue-green algae. Produces energy through photosynthesis. Autotroph. Prokaryote.
Benthos
Flora and fauna found on the bottom of oceans, lakes an other bodies of water.
What forms the base of most food chains?
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Rmax
Maximum population growth rate (i.e. birth rate minus death rate).
Gleason
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Clements
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Does energy stay in ecosystems?
It released into the atmosphere. On the other hand, the matter stays in the ecosystem. i.e. the nitrogen carbon and other nutrients in our bodies are decomposed and used again.
Does matter stay in ecosystems?
Yes, the nutrients stay in the ecosystem after decomposition and are used again. The energy is released into the atmosphere.
Cellular respiration?
Conversion of biochemical energy into ATP, which is necessary for a diverse array of biological processes that keep autotrophs alive.
Is growth and reproduction the dominant drain on an organism’s energy?
No, autotrophs use energy for cellular respiration first and use the remainder for growth and reproduction.
What is NPP?
Net Primary Productivity. The total amount of energy invested by autotrophs in growth and reproduction after, via cellular respiration, they have produced enough ATP to stay alive.
What is GPP?
Gross Primary Productivity. It is the total amount of chemical energy produced in a given area is a given time period.
What is the equation for NPP?
GPP-R=NPP
where r is the energy used in cellular respiration or lost.
What does NPP represent for an ecosystem?
It represents the total amount of energy stored in organic material or biomass. It is critically important to understand because it is the amount of energy available from primary producers to the rest of the organisms in the ecosystem.
What are the two types of food chains?
Grazing Food Chains and Decomposer Food Chains
Do the decomposer and grazing food chains merge at the higher tropic levels?
Yes! For example robins will often eat crickets or earthworms. Crickets get their energy form live Maple leave and are thus part the grazing food chain. Whereas r earthworms get their energy form bacteria, which in turn for from dead leaves and is thus apart of the decomposer food chain.
