Midterm 2

Question 1

Exponential growth

Answer 1

dN/dt = rN
(change in population size/per unit time)= equals intrinsic growth rate* current population size

Question 2

Exponential growth under pop size

Answer 2

Nt=N0e^rt
(pop size at time t)=(starting pop size)(base of natural log: 2.718)(intrinsic growth rate multiplied by time)

Question 3

r>0

Answer 3

birth rate is higher than death rate, gets steeper as time goes on

Question 4

r=0

Answer 4

no change

Question 5

r<0

Answer 5

population declines quickly

Question 6

Mark-recapture

Answer 6

capture some individuals & visually tag or mark them, release marked animals, wait long enough for them to evenly spread throughout population, recapture 2nd set of individuals, see how many are marked

Question 7

N=MC/R

Answer 7

N: total population size
M: # caught, marked & released (1st sampling)
C: # caught in (2nd sampling)

Question 8

Density-independent controls

Answer 8

Factors affecting population size that DO NOT depend on # of organisms in population, usually abiotic factors (Storms, drought)

Question 9

Density-dependent controls

Answer 9

Factors affecting population size that DO depend on # of organisms, usually biotic factors, prevent population from growing forever, (Disease, predation, limited resources(space))

Question 10

Logistic Growth

Answer 10

dN/dt = rN0[(K - N0) / K]
change in population equals intrinsic growth rate times current population size times a factor that shrinks as population approaches K

Question 11

N0 is large

Answer 11

(K-N0)=0, (K-N0)/K=0, growth is slow

Question 12

N0 is small

Answer 12

(K-N0)/K=1, growth is mostly exponential

Question 13

Population size under logistic growth

Answer 13

Nt=(K)/1+[(K-N0)/N0]e^-rt
As N0 nears K, (k-N0) becomes 0
Larger r will take less time (t)

Question 14

K

Answer 14

environmental carrying capacity

Question 15

Survivorship (I_x)

Answer 15

proportion of individuals surviving from birth to age class x
l_x= N_x / N_0 (# individuals / original population)

Question 16

Type 1

Answer 16

high survivorship at early ages & survive to old age

Question 17

Type 2

Answer 17

straight linear line down & similar fraction of individual surviving each age

Question 18

Type 3

Answer 18

straight linear line down & similar fraction of individual surviving each age

Question 19

Fecundity (m_x)

Answer 19

average # of offspring an individual will produce during age class x
m_x= N_x offspring / N_x : (# of offspring / individual)

Question 20

Net reproductive rate (l_x m_x) R_0

Answer 20

mean # of offspring produced per individual across their lifetime
Or average # of offspring per individual
l_x * m_x : (survivorship * fecundity)
Then add all of them together (sigma)
R_0 = (sigma) l_x * m_x

Question 21

Generation time

Answer 21

average difference btwn age of parents & offspring
xl_xm_x : (age * net reproductive rate)
G= (sigma) xl_xm_x / (sigma) l_x * m_x
result should be around age where organism produces most

Question 22

Intrinsic growth rate (r)

Answer 22

Growth rate of population as whole
R = ln(R0) / G
Iow R = ln (net reproductive rate) / ((age * net reproductive rate)/net reproductive rate))

Question 23

Aristotle’s Scala Naturae (350BCE)

Answer 23

very hierarchical & didn’t incorporate any mechanism for change in species through time

Question 24

Zhyang Zhou (369-286BCE)

Answer 24

“species change over other time, even into other species”

Question 25

Al-Jahiz & Al-Biruni

Answer 25

organisms seem to fit in their particular environment, world is limited & there is only so much resources

Question 26

Ibn Khaldun’s Muqaddimah (1377)

Answer 26

Idea that there are processes of decent, individuals down line of descent look diff from ancestors
Descend from monkeys & recognizes inheritance over many generations

Question 27

Linnaeus’ Systema Naturae (1758)-Linnaeus’ Homo Variant

Answer 27

Shared, systematic way of naming & organizing species & their relationships together
Categorizing diversity: write genus w/ capital letter & specie w/ lowercase letter & they are italicized
Divided things into 3 large groups: animals, plants, minerals

Question 28

Alexander von Humboldt

Answer 28

Naturalist who brought global human perspective to climate patterns, identified differences & similarities in species in similar climates
Found similar regions have similar species
Thought everyone w/in human was equal

Question 29

Cuvier & Scientific Racism

Answer 29

Paleontologist who identified patterns of fossils in diff rock layers
His explanation for changes in fossils was that there were period of catastrophes that made 1 species extinct, then another migrated into region

Question 30

Mary Anning

Answer 30

Amatuear fossil collector

Question 31

Catastrophism

Answer 31

Earth & life on it primarily shaped by major, sudden events
Sudden changes in fossil records, minerals, volcanic eruptions

Question 32

Gradualism

Answer 32

Earth & life on it are primarily shaped by long, slow processes
Similar changes, fossils look similar, incremental changes

Question 33

By mid 1800s

Answer 33

Generally accepted that:
Gradual change is important component of Earth’s history
Earth is very old (Lord Kelvin estimated at 100 my)
Extinction occurs

Question 34

Jean-Baptiste Lamarck

Answer 34

believed organism passed on traits that acquired through use/disuse