1. Chapter 4
Biodiversity

2. Indicator Species
article about indicator species

3. Biodiversity Is the variety of life on Earth
What land biome has the most variety of life on earth?
Tropical Rainforest – covers about 7% of Earth’s land surface and contains half of the plant and animal species found on land

4. Biodiversity Includes 4 different ways to define it specifically
- variety of Earth’s species
- variety of genetic material species contain
- the ecosystems on Earth
- the ecosystem processes such as energy flow and nutrient cycling

5. Species Diversity
The variety of species in a specific ecosystem and their abundance (how much of them)
About 2 million species of organisms have been identified so far. Scientists think there may be 7-10 million up towards 100 million species.

7. How to calculate species diversity?
the number of species in the area (numerator) = biodiversity the total number of index individuals in the area (denominator) Values range from 0 to 1.

8. Examples
For example, a 4 X 4 meter square area in a carrot patch has 300 carrot plants, all the same species. It has a very low biodiversity index of
1/300, or
A 4 X 4 meter square area in the forest has 1 pine tree, 1 fern, 1 conifer tree, 1 moss, and 1 lichen, for a total of 5 different species and 5 individuals. The biodiversity index here is high,
5/5 = 1.

9. Genetic Diversity
The variety of genes found in a population or in a species.
Genes get passed to offspring through reproduction. We call them traits.
Species have a better chance of surviving/adapting to environmental changes if there is greater genetic diversity.

10. Variety in a species of peppered moths
Before the Industrial Revolution, trees had light bark, so light colored moths survived more often.
After the Industrial Revolution, trees had dark colored bark from the pollution, so dark colored moths survived more often.

11. Ecosystem Diversity
Earth’s diversity of biomes like deserts, grasslands, forests, lakes…
Biomes are characterized by:
-Climate (temperature and precipitation)
-types of vegetation

12. Functional Diversity
The variety of processes such as energy flow and matter cycling within ecosystems.
For example: How many herbivores does an ecosystem contain? If one was removed, would the ecosystem continue thriving or be damaged?

13. Biodiversity More biologically diverse ecosystems are:
-more productive
-more stable
-more likely to include species with traits that enable them to adapt to changes like disease or drought
This is called the insurance hypothesis.

14. Biodiversity and Natural Capital
With biodiversity, natural capital is maintained.
We grow food and make medicine.
Natural ecosystem services are supported like renewal of topsoil and pollination, and decomposition of wastes.
With genetic variety, we can ensure our organisms can respond to environmental changes.

15. Roles in an Ecosystem
Besides being an autotroph or heterotroph in an ecosystem, species have to fit into their environment in order to find enough food, find shelter and try to reduce competition. Each species has a:
ecological niche – a species way of life
habitat – place where it lives

16. Niche or habitat A giraffe feeds on the canopy of trees.
The giraffe lives in the Savannah.
A squirrel is an omnivore.
A squirrel lives in a forest.
A bee makes honey and pollinates flowers.
A deer keeps grass and shrubs under control.

17. Niche
Each species can be broken into categories based on how it lives.
Generalist species: broad niche
- can live in many different places
- eat a variety of foods
- tolerate a wide range of environmental conditions
Can you think of an organism that this describes?

18. Niche Specialist species: narrow niche
- can live in only one type of habitat
- eat only one or a few types of food
- tolerate a narrow range of environmental conditions
- are more likely to become endangered or extinct with changes in their environment
Can you think of an organism that this describes?

19. Youtube
generalist vs specialist video

20. What happens when niches overlap?

21. Native vs nonnative species
Native species are those that naturally originated in a given ecosystem
Nonnative species have been introduced to an ecosystem that they have not originated from
-introduction can be natural or by human actions

22. Nonnative species Other names for this type of species: -alien, exotic
When nonnative species cause problems in their new environment, then they are called invasive species.
They compete with native species for food and shelter, can cause economical damage, and spread diseases.

23. Keystone Species
They are the key to the health of an ecosystem. Without them, the ecosystem would be different or collapse.
Who would be a keystone species in our environment to control the whitetail deer population size?

24. Pg 113 American Alligator Read and answer questions below:
1. List and give a brief description of all the ecological services that the American alligator does for its ecosystem. (At least 7 services)
2. What actions have humans done to make the American alligator almost extinct?
3. What did the U.S. government do to protect them and did it work?

25. Indicator Species
The presence or absence of this species indicates the quality of certain environmental conditions.
These species are sensitive to environmental changes and are affected immediately. They provide an early warning to humans that the environment is deteriorating.
Give an example of an indicator species.

26. How are humans affecting indicator species?
Humans compete with other species for resources, so our niches overlap and we see a population decline. What are we doing to other species?
- hunting, poaching
- moving species creating invasives
-eating/making products with species
-fragmenting habitats/changing ecosystems
-destroying the ozone layer
- releasing chemicals and pollution

27. Change over time
Evolution is the process by which species genetically change over time.
-genes of a population change from generation to generation
Natural selection is the process individuals with certain genetic traits are more likely to survive and reproduce under certain environmental conditions.

28. Variety in a species of peppered moths
Before the Industrial Revolution, trees had light bark, so light colored moths survived more often.
After the Industrial Revolution, trees had dark colored bark from the pollution, so dark colored moths survived more often.

29. Natural Selection
Involves changes in a population’s genetic makeup through successive generations.
It is also called “Survival of the fittest”.

31. Genetic Variability
Genetic variability is the variety in the genetic makeup of individuals in a population.
Variety is caused by mutations which is a permanent change in the DNA sequence. Only mutations within the reproductive cells may be passed on to offspring.

32. Natural selection is an editing process, whereby inherited characteristics provide a wide range of phenotypes, while environmental factors eliminate those that are not well-suited to the environment.  

33. Phenotypes

34. Genetic Variability
Populations develop genetic differences among their individuals.
Natural selection operates on populations, not individuals.
It affects the phenotypes which survive and reproduce and which do not.
Genetic testing is big business right now.

35. Genetic Variability
When individuals have survived and reproduced, they are said to be better suited to the environment than others in their population. These individuals have an adaptation that was inherited by their parents.
Adaptation gives an individual some advantage over other individuals in a population.

36. Genetic Resistance
Resistance is the ability of one or more organisms to tolerate a particular chemical designed to kill it.
Give an example of something you know has resistance.

37. Genetic Resistant Bacteria

38. Genetic Resistant Bacteria

39. Antibacterial soap
resistance in antibacterial soap video

40. Limitations to natural selection
If there is an environmental change in the future, then life can only adapt if the genetic traits are already in a population’s gene pool or if adaptations needed can happen through random mutations.
If the adaptation is in the gene pool, then the limit is how fast a population can reproduce to make new offspring.

41. What affects biodiversity?
Speciation the process when one species evolves into two or more different species.
Can occur when:
-geographic isolation: population gets split by a barrier or natural event
- reproductive isolation: once separated, populations don’t share genes through reproduction anymore

43. Extinction Occurs when an entire species ceases to exist.
When an entire species cannot adapt to environmental changes or move to a new environment, it will become extinct.

44. Endemic Species Species found in only one area Example: Vulnerable to
Extinction!!
Smaller population
gene pool, so a population has a harder time adapting to environmental changes.

45. Extinction
99.9% of all the species that have existed on Earth are now extinct.
Extinction has occurred at slow rates and at faster rates over Earth’s history.
Mass extinction is a time when extinction is at a faster rate. Earth has experienced 5 mass extinctions during the last 500 million years.

46. Mass Extinctions

47. Mass Extinction Possible natural causes: -volcanic eruptions
-collisions with giant meteors
Both could block out the sunlight for a long period of time and release greenhouse gases
After each mass extinction, an increase in species diversity has been shown in the fossil record.

48. Biodiversity
Earth’s biodiversity = speciation + extinction
Scientists say Earth is entering a 6th mass extinction which link human activity as the cause.

49. 6th Mass Extinction
6th mass extinction nat geo article

50. Humans can play with nature
Humans can selectively manipulate genes in order to enhance adaptations of organisms to better meet human needs.
Artificial selection is when humans change the genetic characteristics of populations.
-We select the desirable trait that exists in the population already. We control which organisms breed.

51. Humans can play with nature
Newer hybrids like the Labradoodle, a mix between a Labrador retriever and a poodle are in high demand. Most people who like these hybrids enjoy the uniqueness and the look of these new breeds.

52. Human can play with nature
Our food has been “tweaked” for many years. Most of our fruits, grains, and vegetables have been artificially selected for desirable traits.
It is limited to the same species or species that are genetically similar. We cannot have this:

53. Genetic Engineering Scientists can use this to select
for desirable traits or eliminate undesirable ones.
This is when scientists alter the organism’s DNA by adding, deleting, or changing segments of its DNA. This is not limited to the same species. New organisms are called genetically modified organisms (GMOs).

54. GMOs GMO video Do you look for non-GMO food when you shop?
Do you buy 100% organic foods?
The US government banned GMO labels on food, but companies can label food 100% organic.