Download Grade 9 Science – Unit 1 – Biology

Grade 11 University Biology – Unit 1 Diversity
Classifying Types of Diversity
Section 1.4 – Pages 31-37
Biodiversity refers to the variation of all living organisms in a given local, regional or global area
considered at a multiple levels of organization and from a range of different perspectives.
In your own words and using the attached pictures and your textbook, define each category of diversity.
Category
Species
Diversity
Your Definition


Genetic
Diversity
Ecosystem
Diversity
Variety and abundance of a species in a
given area
Number of different species in a given
area, their relative distribution and their
relative proportions
Illustration
Category
Your Definition
Compositional
Diversity
Structural
Diversity
Functional
Diversity
Question - Why is Diversity Important?
Illustration
Genetic Diversity

Genes are the genetic material that controls the expression and inheritance of traits. Individual variation is
generally the difference in genes. Genetic Diversity within a population is the GENE POOL (i.e., all the
genes of all the individuals in a population). A POPULATION is a group of individuals of the same species
in a given area at a specific time.

Genetic Diversity is generally greater within a species than a population. Why?


Genetic Diversity is vital to disease resistance. Populations with limited genetic diversity are more prone to
disease. If all individuals have the same genetic makeup and are susceptible to a disease, the population
will likely go extinct.
Genetic Diversity also allows populations and species to survive changing environmental conditions (e.g.,
climate changes)
Ecosystem Diversity

This refers to the variety of ecosystems in the biosphere. ECOSYSTEM consists of all the organisms living
(biotic) in a given area, plus the non-living (abiotic) physical components of the environment (e.g., soil,
water, sunlight, latitude) in which the living organisms interact. Ecosystems can be very small or very large.

BIOSPHERE is the variation of life forms on Earth.

Due to the variety of interactions among organisms and the wide range of abiotic factors, ecosystem
diversity on Earth is very high.
TASK


Do Activity 1.3 – Sustainability and Diversity: Find a Balance? on Page 33
The following information will help you address the questions.
Paraphrased from -
Science Daily. 1 March 2010. Pesticide Atrazine can turn Male Frogs into Females. (Online). Available http://www.sciencedaily.com/releases/2010/03/100301151927.htm

Trivedi, Bijap P. 16 April 2002. Hermaphrodite Frogs caused by Popular Weed Killer. National
Geographic News. (Online). Available http://news.nationalgeographic.com/news/2002/04/0416_020416_TVfrog.html
Atrazine, one of the world's most widely used pesticides, wreaks havoc with the sex lives of adult male
frogs, emasculating three-quarters of them and turning one in 10 into females
“The 75 percent that are chemically castrated are essentially dead because of their inability to
reproduce in the wild. These male frogs are missing testosterone and all the things that testosterone
controls, including sperm,” reports University of California Biology Professor Tyrone Hayes.
“Their fertility is as low as 10% in some cases, and that is only if we isolate those animals and pair
them with females. In an environment where they are competing with unexposed animals, they have
zero chance of reproducing," Hayes said.
The 10% or more that turn from males into females - something not known to occur under natural
conditions in amphibians - can successfully mate with male frogs but, because they are genetically
male, all their offspring are male.
"When we grow these guys up, depending on the family, we will get anywhere from 10 to 50 percent
females," Hayes said. "In a population, the genetically male females can decrease or wipe out a
population just because they skew sex ratios so badly."
Though the experiments were performed on a common laboratory frog, the African clawed frog
(Xenopus laevis), field studies indicate that atrazine, a potent endocrine disruptor, similarly affects frogs
in the wild, and could possibly be one of the causes of amphibian declines around the globe, Hayes
said.
Hayes concludes that atrazine is a likely contributor to worldwide amphibian declines. Hayes notes,
"These kinds of problems, like sex-reversing animals skewing sex ratios, are much more dangerous
than any chemical that would kill off a population of frogs. In exposed populations, it looks like there are
frogs breeding but, in fact, the population is being very slowly degraded by the introduction of these
altered animals."
The USA EPA has set the limit for atrazine contamination for drinking water at 3 parts per billion (ppb).
Hayes' and his colleagues found that concentrations of 0.1 ppb caused abnormalities. Tadpoles of the
African clawed frog were exposed to atrazine at concentrations as low as 0.1 ppb. When the tadpoles
reached adulthood, between 16 and 20% had abnormal reproductive systems.
"Some had three ovaries and three testes, some had ovaries on one side and testes on the other, one
animal even had six testes," said Hayes. The male voice box also shrunk, resembling the female
version, and when males were exposed to levels as high as 25 ppb of atrazine, the frogs showed a tenfold decrease in testosterone levels. Hayes suspects that atrazine feminizes the frogs by increasing
production of an enzyme called aromatase, which converts testosterone to estrogen.
Some 37 million kilograms of the herbicide atrazine are applied annually in the USA on corn and
sorghum to control weeds and increase crop yield. Such widespread use also makes atrazine the most
common pesticide contaminant of ground and surface water.
Research is showing that atrazine interferes with endocrine hormones, such as estrogen and
testosterone -- in fish, amphibians, birds, reptiles, laboratory rodents and even human cell lines at
levels of parts per billion. Recent studies also found a possible link between human birth defects and
low birth weight and atrazine exposure in the womb.
Ecosystem Services

Ecosystem Services are the benefits experienced by organisms, including humans, provided by sustainable
ecosystems.

See Table 1.6 on Page 34
 Table 1 is a dataset of Beach Day Closings (or “Postings”) at Bay of Quinte beaches between 1988 and
2002. Graph and interpret the data. What value does this data provide with respect to Ecosystem
Services?
Table 1. Bay of Quinte Beach Day Postings per year
Year
Bain Park Frankford Centennial Northport Kingsford Riverside Riverside
Zwick’s
Trenton
Deseronto
Salmon
East
West
Island
River
Belleville
Belleville
Belleville
1988
28
7
0
86
86
0
1989
0
8
0
7
85
81
14
1990
14
14
0
0
68
97
97
43
1991
0
30
0
0
28
211
211
0
1992
8
0
0
0
0
108
98
0
1993
0
0
0
0
121
157
0
1994
35
45
0
0
0
97
97
49
1995
8
0
8
0
0
105
105
11
1996
0
15
6
70
70
7
1997
9
63
15
0
7
60
60
0
1998
0
0
15
8
9
107
107
0
1999
35
17
17
0
7
101
101
0
2000
25
20
17
0
64
64
0
2001
18
62
7
6
104
104
0
2002
7
14
14
0
70
84
0
Source. Quinte Conservation, XCG Consultants and Lower Trent Conservation. 2011. Bay of Quinte Region
Pollution Prevention and Control Plan. Final Report. (Online). Available http://quinteconservation.ca/web/images/stories/protecting_our_watersheds/studies/BQRAP_PPCP/bqrap_p
pcp_report.pdf
Resilience – The ability of an ecosystem to remain functional and stable in the presence of disturbances to its parts

Read Ecosystem Function and Species Diversity on Page 35

Interpret the graphs (Figure 1.21 on Page 35)

Do Thought-Lab Investigation 1-B “Resilience of a Grassland Ecosystem” on Page 39
Questions

Page 33, Questions 20-23 and Page 37, Questions 1-4, 8-9
Classifying Types of Diversity – Teacher Notes
Category
Species
Diversity
Your Definition


Genetic
Diversity


Ecosystem
Diversity


Compositional 
Diversity
Variety and abundance of a species in a
given area
Number of different species in a given
area, their relative distribution and their
relative proportions
Variety of heritable characteristics (genes)
in a population of interbreeding individuals
Variation among the characteristics of
individuals within the species as
determined by their genetic makeup
Variety of species in the biosphere
Combination of different species and the
ensuing populations and community
dynamics that occur in a given area
Based on the different number of elements
in a given system (e.g., total number of
genes within a species, total number of
species in a community)
Structural
Diversity

Based on variation in patterns and
organization of species genetics and
morphology, specific habitats, populations
and communities in a system
Functional
Diversity

Based on the number of variation of
ecological processes (e.g., predator-prey
interactions, decomposition, parasitism
and nutrient cycling) in a given system
Illustration