Principles of Biology: Exam 4 Dr. Jones, Cedarville University

Types of Biodiversity

Genetic Diversity

Species richness in an

ecosystem

Ecosystem diversity

Ecosystem factors

Resources, Climate

Habitat Heterogeneity

Diversity of variety in habitat types.

Tropical Rainforest

Ecosystem/biome that provides the greatest amount of habitat heterogeneity.

species richness and habitat

The type of habitat determines what species live in an ecosystem and its species richness.

Latitudinal gradient

The increase in species richness or biodiversity that occurs from the poles to the tropics.

Benefits of biodiversity to humans

Goods (food, resources), services (recycling minerals, flood control), information (genetic engineering), psycho-spiritual (aesthetic beauty, awe of Creator)

Value of biodiversity

The more options for resources, the more likely the organisms in an ecosystem will be able to survive (larger food web).

H: Habitat Destruction

Medicine for cancer on Madagascar, apex predators at most risk

I: Invasive Species

"Guam" tree snake in bathrooms, zebra mussels eat plankton, round Goby, emerald ash borer, Asian carp and Great Lakes

P: Pollution

Surface water contamination, pavement, greenhouse gasses, runoff, sewage, combustion exhaust, pig farm

P: Population growth (human)

Ecological footprint, carrying capacity, intrinsic rate of growth, medical and industrial revolutions.

C: Climate Change

Greenhouse gases, anthropogenic sources of carbon [fossil fuel combustion, industrial and agricultural processes] increased temperature, changing and increasing precipitation, decrease in size and number of glaciers, deep water temperatures s have increased, Bluefin Tuna present in Arctic waters

O: Overexploitation

Overused resources, CITES act, IUCN lists endangered/ threatened species ESA protects endangered species, society does not look beyond immediate effects.

Species Area Curve

Direct correlation between area size and numbers of species.

Nonnative Species

Species that migrate into an ecosystem or are deliberately or accidentally introduced into an ecosystem by humans. Not necessarily invasive.

Point Source Pollution

Pollution that has a source (sewage plant, "end of the pipe").

Non-point Source Pollution

Pollution over a large area (agricultural runoff [plant and animal], urban runoff [urban development and sprawl]).

Pavement (impervious surface)

Increased flooding, channel erosion, pollutants.

Deforestation

Removal of trees that results in increased erosion (roots hold soil in place).

Erosion

Natural process that wears away at soil and makes it less fertile.

Acid deposition

Sulfur oxides and nitrogen oxides, emitted by burning fossil fuels, enter the atmosphere-where they combine with oxygen and water to form sulfuric acid and nitric acid-and return to Earth's surface. Acid rain pH number in the soil and aquatic systems

Eutrophication

Enriching of water (algal blooms result in biomagnification, etc.).

Monoculture

An ecosystem with only one population.

Agriculture Rationale

The efficiency of supplying food supports large populations. It is a monoculture that results in the arrest of weeds, broken cycles (no natural process of succession), and no point source pollution to control runoff.

Ecologial footprint

Amount of natural resources needed to supply a population with the necessities of life in a given area to sustain the current quality of life.

Sustainable resources

Resources that are replaced at the same rate as they are exploited (renewable). Natural resource degradation, recycling natural resources.

Grain Diet

Makes a pyramid with just two layers while a meat-based diet has three layers. With less layers, the initial grain an be more productive, but if has to go through a middle (such as cattle), energy is lost and not as effective.

Evidence of Climate Change

Increased global temperature, changing and increasing precipitation, decrease in size and number of glaciers, rising sea levels, deep water temperatures increasing, Bluefin Tuna in Arctic waters.

Controversy of Climate Change

Many conservationalists blame humans for climate change and sometimes desire to go to drastic measures to stop it (genocide, etc.), predictions versus actual data.

CITES

Convention on International Trade in Endangered Species of 1975: Makes it illegal to export or import elephant ivory, rhino horns, tiger skins, live endangered birds, lizards, fish, and orchids; anything produced by or currently endangered.

IUCM

The International Union for Conservation of Nature and Natural Resources lists 17,741 endangered and threatened species: Nearly one-fifth of mammals, nearly one-third amphibians, replies, fish.

Hhas no direct jurisdiction for slowing the loss of those species. Within the United States, the ESA provides mechanisms for reducing species losses.

ESA

The Endangered Species Act, protects biodiversity and targets habitats that are at risk. Provides criteria for species at risk, direction for planning recovery, assistance to landowners to help them find ways to help both populations, and enforcement of measures to protect species and their habitats.

ESA Successes

The brown pelican, the peregrine falcon, the American alligator and the bald eagle.

ESA Controversies

The Tennessee Valley Authority and the snail darter, and with the timber industry and the northern spotted owl.

Biodiverity hotspot

An area with exceptional concentration of diverse species and unusually high endemic. They are important because they are said to be the area where evolution is occurring.

Endemic species

Species found in only one location, such as the Siberian tiger, macaw, etc.

Factors of environmental crisis

Resource depletion and pollution are the keys to the current ecological crisis, as caused by industrialization and the ecological footprint.

Ethics (Aldos Leopold)

Ethics constrains self serving behavior in deference to some other good.

Intrinsic value

Value in and of itself - does not arise from utility. Creation is considered valuable by divine decree.

Instumental value

Value that takes a utilitarian approach as a mere means to human ends.

Principle of Mass Balance

Must account for the mass of nutrients or contaminants that are introduced or removed in an ecosystem. This reflects the law of conservation. The nutrients or contaminants if introduced into as system will remain where they are in their original form, move elsewhere via a transport process, and undergo a biochemical transformation into a another substance (CO2 to glucose).

Cost-Benefit analysis of conservation

Does the benefits of using natural resources outweigh the cost of HIPPCO?

Oparin's hypothesis

Life originates from non-living matter in a series of gradual

steps: simple chemicals, monomers, polymers, cell.

Miller-Urey Experiment

Demonstrated

that complex molecules

can spontaneously form

from simple chemicals

Embyrology inferences

Embryos of all vertebrates have deep structural similarities and these deep similarities are said to clearly show evidence for evolutionary relationships.

Early stages of vertebrate embryos exhibit features common to the phylum before developing the distinguishing characteristics.

Hourglass Conundrum

Vertebrate embryos are most similar to each other in middle phase of development, but vary greatly during earliest and latest stages of development.

Haeckel's Embryos

Haeckel drew similar-looking embyros that supposedly represented a number of species in early development. These drawings misrepresented the

features of the embryos, exaggerating their similarities. Despite this, his drawings are used in biology textbooks

and encyclopedias to this day.

Macroevolution observations in the fossil record

1. Fossilized simple creatures

would be found in the older

layers of sedimentary rock

and the more complex (or

higher evolved) should occur

in the younger layers of

sedimentary rock.

2. Links between the simple

organisms in the bottom

layers and the more complex

in the above layers.

Mayr-Gould view of fossil record and transition forms

Fossil record seems to document saltations (jumps) from one

type of organism to another.

Mayr-Gould explanation of fossil record issues

Fossil record is one of discontinuities (gaps) in what should be continuous, gradual and steady changes from ancestral forms to the descendants. General picture is that no fossil connecting links occurs between most groups of animals and in plants the lack of connecting links is more pronounced. Only a small fraction of organisms that once lived are fossilized. Highly improbable that any organisms become fossilized.

Gould' punctuated equilibrium

Species change quickly followed by periods of stagnation (bottlenecks and founder's effects). Rests upon Cambrian explosion. Seems to support Polyphyletic view of the hstory of life.

Polyphyletic view of life

Multiple common ancestors, one for each "kind."

Molecular Homologies

Similarities at the molecular level that indicate that living species evolved from a common ancestor or interrelated group of common ancestors.

Cytochrome C

Molecule found in virtually all organisms - electron transport protein found in mitochondria. Changes in amino acid sequence in the protein between species over time. The amount of homology determines how close together different groups are.

Criticisms of Molecular Homologies

Organisms that are more distantly related have accumulated a greater number of difference in their genomes, similar genes, and amino acid sequences in proteins. An evolutionary tree is constructed based upon the principle that the more similar the nucleotide sequence, the more closely related the species.

Denton's re-organizing of the cytochrome c data critique

One gene gives one version of the tree of life, while another gene gives a highly different, and conflicting, version of the tree.

The standard mammalian tree places humans more closely related to rodents than to elephants. But studies of a certain type of DNA called microRNA genes have suggested the opposite --that humans were

closer to elephants than rodents. Such conflicts between gene-based trees are extremely common.

Comparative Morphology

Similarities and differences in body plans/structures among groups of different organisms: Parts of different organisms that serve different functions but have the same internal structure and develop from the same embryological pathway. Inferred that the correspondence of different features in different organisms is due to inheritance from a common ancestor. Inherited the structure from an ancestor then evolved modifications to adapt to the needs of the individuals

Mayr's comment about homologies

Homology cannot be proven, it must be inferred.

Interventionist look at the evidence of morphological homologies.

Non-homologous structures

should be regulated by non-

homologous genes. Human, cephalopod, & insect eyes -BUT NO.

Homologous structures should be built by homologous genes: Fruit Fly vs. Wasp, Vertebrate gut BUT NO!

Incongruence between phylogenies derived from

morphological versus molecular analyses, and between trees based on different subsets of molecular sequences has become pervasive as datasets have expanded rapidly in both

characters and species.

irreducible complexity

Many structures and processes in living things have so many interdependent parts and steps in their actions that they could not operate unless all the components were present simultaneously in their finished state. Something that is so amazingly complex, it had to be fully formed and functional from the beginning or it could not exist at all (Behe).