2 3 Measuring Biotic Components What is classification
2. 3 Measuring Biotic Components
What is classification? �Science of grouping organisms based on their physical characteristics.
What characteristics do we use? �Structures (morphology) �Functions (physiology) �Biochemistry �Genetics
Why do we classify? �Identify organisms �Compare organisms �Identify relationships among organisms �Communicate with others (universal language) �Identify evolutionary relationships
Why do we classify? �What am I? �Firefly �Lightning bug �Glow Fly �Blinkie � Golden Sparkler �Moon bug �Glühwürmchen �Luciérnaga �Luciole �We all have different names for the same organism…this is a problem for communication.
Same or different?
From Aristotle to Linneaus �Aristotle (Greek philosopher) (384 -322 B. C) First System of Classification � 1. Plants Based on stem type � 2. Animals Land, air or water
From Aristotle to Linneaus �Carolus Linneaus (Swedish botanist) (1707 -1778) Came up with modern classification system Used binomial nomenclature (2 word naming system) This two word name is called a scientific name Composed of the genus name followed by the species name
Scientific Names �Either written in italics or underlined �Genus is always capitalized and species is always lowercase �Based on Latin �Examples: Cat: Felix domesticus Mosquito: Colex pipens Human: Homo sapien
Funny Scientific Names �Agra vation (a beetle) �Colon rectum (another beetle) �Ba humbugi (a snail) �Aha ha ( a wasp) �Lalapa lusa (a wasp) �Leonardo davinci (a moth) �Abra cadabra (a clam) �Gelae baen, Gelae belae, Gelae donut, Gelae fish, and Gelae rol (all types of fungus beetles) �Villa manillae, Pieza kake and Reissa roni (bee flies)
Dichotomous Keys �A series of yes/no questions about an organisms structure �Used to identify new and unknown organisms
Estimating Populations of Organisms �We estimate populations because it would take way too long to count every living thing in a given ecosystem. �We can estimate populations of plants or animals �Random Sampling: All organisms must have an equal chance of being captured.
Estimating Populations of Animals �Lincoln index (capture-mark-release-recapture) n 1 x n 2 N = n 3 • N = Total number of population • n 1 = Number of animals first (mark all of them) • n 2= Number of animals captured in second sample • n 3= Number of marked animals in second sample Ex. 40 mice were caught, marked (tail tattoo) and released. Later, 10 mice were recaptured, 4 of which had tattoo marks.
Lincoln Index
Lincoln Index Practice Problem �An ornithologist captured 450 finches, marked them with an ankle band released them. One week later she recaptured 237 finches, 50 of which had ankle bands. What is the total finch population?
Lincoln Index Assumptions 1. 2. 3. 4. 5. 6. The marked animals are not affected (neither in behavior nor life expectancy). The marked animals are completely mixed in the population. The probability of capturing a marked animal is the same as that of capturing any member of the population. Sampling time intervals must be small in relation to the total time of experiment of organisms life span. The population is closed (no immigration and emigration) No births or deaths in the period between sampling.
Estimating Populations of Plants �Quadrat Estimation Population Density- The number of plants within the given area of the quadrat (m 2) Percentage Coverage. How much of the area of a quadrat is covered by plants? Percentage Frequency- How often does a plant occur in each quadrat? �Acacia senegalensis was present in 47 of 92 quadrats, for a frequency of 51%
Calculate Population Density What is the population density of species x ? What is the population density of species Y? Quadrat 1= 0. 5 m 2 What is the population density of species Z? X X X W W W X X W X W W Z W W Y
Calculate Percentage Coverage What is the percentage of plant coverage in this quadrat? Quadrat 1= 1 m 2 X W X W X X X W W Y
Percentage Frequency Quadrat 1 What is the frequency of species X? What about species V? X W W W X X X X V W W X X W W Z W W Y Quadrat 2 Quadrat 3 Z X W X X W W W X W Z W X X W Z W W X W W W Y W Z W W Y Z Z Z W W W Z Z Z W X W Z
Estimating Biomass of Tropic Levels �Take a sample from one area and assume the organisms are evenly spread out through the area. Biomass (dry weight) of living tissue �We use dry weight because water is non-living and needs to be excluded �Ex. 1500 g of ferns were sampled in a 100 m 2 area. How many ferns would be in 1000 m 2 field in the same ecosystem?
What is diversity? �Diversity is the variety of life �Diversity is a combination of two components Evenness: The number individuals of each species present in a sample Richness: The total number of different species in a sample
How Can We Know Diversity? Use the Simpsons diversity index below D = ______N (N-1)________ n 1(n 1− 1) + n 2(n 2 − 1) + n 3(n 3 − 1) +…nk(nk − 1) D = Diversity N = Total number of organisms of all species n = number of individuals of a particular species ***The higher the D value the more diverse the sample is!!!!!
Example Data Calculations Abundance of Organism Ecosystem A Ecosystem B species 1 3 5 species 2 7 4 species 3 26 12 species 4 9 7 species 5 7 0 Diversity 3. 27
Sample Calculation Number of Organisms species 1 Ecosystem B 5 species 2 4 species 3 12 species 4 7 species 5 0 Diversity
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