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Population Ecology I— Population structure and distribution; life-history trade-offs and reproductive strategies. Opening photo, Unit 2. Cain et al. (p. 153). Unitary and modular organisms— What is an individual?. Examples of modular organisms—. Fig. 9.1, Smith & Smith, 6 th ed. (p. 187).
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Population Ecology I— Population structure and distribution; life-history trade-offs and reproductive strategies Opening photo, Unit 2. Cain et al. (p. 153)
Unitary and modular organisms— What is an individual?
Examples of modular organisms— Fig. 9.1, Smith & Smith, 6th ed. (p. 187) A quaking aspen (Populus tremuloides) genet A shoal grass (Halodule beaudettei) genet
How might modularity affect population studies? • All the trees in this photo are trembling aspens. How many individuals do you see here? Photo by Loraine Yeatts
How might modularity affect population studies? • Apart from the dark green conifers, most of the trees in this photo are trembling aspens. How many individuals are there in this population? Photo by Loraine Yeatts
An expanding population of a clonal plant— • New ramets are initially physiologically dependent on the parental ramet, but later often become self-sufficient. Fig. 9.2, Smith & Smith 6th ed. (p. 188)
Two examples of modularity in animals— Clones of (a) a coral and (b) a sponge Fig. 9.3, Smith & Smith 6th ed. (p. 188) Fig. 9.2, Smith & Smith (5th ed), p. 172
Most species have relativelysmall geographic ranges— • as illustrated by (a) 1,370 spp of North American birds, and (b) 1,499 spp. of British vascular plants. Fig. 50.27, Campbell & Reece, 6th ed. (p. 1118)
Geographic range of the red maple (Acer rubrum) Fig. 9.4, Smith & Smith, 7th ed. (p. 185)
Geographic range and relative abundance of the Carolina wren (Thryothorus ludovicianus) Fig. 9.5, Smith & Smith, 5th ed. (p. 175)
General representation of the dispersion of individuals in a population within its local distribution (or, range) Fig. 9.3, Smith & Smith, 7th ed. (p. 185)
Distribution of the moss (Tetraphis pellucida) at several spatial scales Fig. 9.5, Smith & Smith 7th ed. (p. 186)
Distribution of the horned lark (Eremophila alpestris) at several spatial scales— • What factors might promote patchiness in distribution at each scale? Fig. 9.6, Smith & Smith (5th ed), p. 176
Distribution is partly a matter of dispersal— • Human-assisted dispersal of kudzu (Pueraria montana) There’s a kudzu photo in your text (p. 196), but this one is more dramatic.
Boom-and-bust populations— • Gypsy moth (Lymantria dispar), scourge of the Eastern deciduous forests of North America (Coming soon to a forest near you??) Fig. 1 (Ch. 9), Smith & Smith 6th ed. (p. 201)
Boom-and-bust populations— • Gypsy moth (Lymantria dispar), scourge of the Eastern deciduous forests of North America (Coming soon to a forest near you??) Fig. 1 (Ch. 9), Smith & Smith 6th ed. (p. 201)
Boom-and-bust populations— • Gypsy moth (Lymantria dispar), scourge of the Eastern deciduous forests of North America (Coming soon to a forest near you??) Temporal and spatial changes in population distribution of gypsy moth. Fig. 9.17, Smith & Smith 7th ed. (p. 194)
Spatial dispersion of individuals within a population— • What might promote a specific pattern in a particular species population? Fig. 9.8, Smith & Smith 6th ed. (p. 191)
Spatial dispersion of individuals within a population— • What might promote a specific pattern in a particular species population? Fig. 52.2, Campbell & Reece (6th ed)
An example of uniform dispersion— • shrubs on the Kara Kum desert Fig. 9.9, Smith & Smith 6th ed. (p. 192)
Clumped dispersion within a uniform dispersion— • the shrub Euclea divinorum growing in the shelter of Acacia tortilis trees Fig. 9.10, Smith & Smith 6th ed. (p. 192)
Why all the clumping? Fig. 52.1, Campbell & Reece, 6th ed. (p.
Age structure (and recruitment?) in an oak (Quercus) population in Sussex, England Fig. 9.15, Smith & Smith 6th ed. (p. 198)
Reproductive Strategies:Life-history trade-offs in patterns of reproduction Opening photo for Ch. 8 in Smith & Smith 7th ed. (p. 158)
Precocity vs. delay— Precocious reproduction in dandelion (Taraxacum officinale) What ecological circumstances might favor each of these strategies? Delayed reproduction in red oak (Quercus rubra)
Semelparity vs. iteroparity— Fig. 52.6, Campbell & Reece 7th ed. (p. 1141) • Agave (Agave sp.)— • a semelparous plant What ecological circumstances might favor each of these strategies? • Sugar maple (Acer saccharum)— • an iteroparous plant
Semelparity vs. iteroparity— Fig. 7.11, Cain et al. (p. 162) • Agave (Agave sp.)— • a semelparous plant?
Fecundity vs. parental care— What ecological circumstances might favor each of these strategies? Fig. 52.8, Campbell & Reece 7th ed. (p. 1142) a. Dandelion (Taraxacum officinale): High fecundity, little “parental care” per individual embryo. What animal species have life-histories characterized by these strategies and the ones in the preceding slides? b. Coconut palm (Cocos nucifera): Much lower fecundity, much greater parental investment in each embryo.
Contrasting life history strategies in two salamander species with overlapping ranges Left: spotted salamander (Ambystoma maculatum) Fig. 8.17, Smith & Smith, 7th ed (p. 176) Right: redback salamander (Plethodon cinereus)
Evidence for the trade-off between fecundity and parental care: • Inverse relationship between mean seed weight and fecundity in a variety of herbaceous plants. Fig. 7.15, Cain et al. (p. 165)
Evidence for the trade-off between fecundity and parental care: • Inverse relationship between mean seed weight and fecundity in goldenrod. Fig. 8.12, Smith & Smith, 7th ed (p. 170)
The cost of reproduction in lesser black-backed gulls— • Effectsof experimental manipulation of brood size on survival of offspring Fig. 7.14, Cain et al. (p. 165) Fig. 52.7, Campbell & Reece 7th ed. (p. 1142)
The cost of reproduction in European kestrels— • Effectsof experimental manipulation of brood size on survival of parents Fig. 52.7, Campbell & Reece 7th ed. (p. 1142)
Cost of reproduction in red deer on the island of Rhum in Scotland— • Effects of reproduction on mortality of females Fig. 52.5, Campbell & Reece 6th ed. (p. 1157)
Another way to look at the metabolic cost of reproduction— • Relationship between fecundity and size of big-handed crabs in New Zealand Fig. 8.13, Smith & Smith, 7th ed. (p. 171)
Another way to look at the metabolic cost of reproduction— • Relationship between fecundity and size of European red squirrels Fig. 8.13, Smith & Smith, 7th ed. (p. 171)
Using mark-recapture sampling to estimate animal populations— • (or, How to determine populations of “uncooperative organisms”)
Using mark-recapture sampling to estimate animal populations • Imagine you are studying a particular species of fish, and there is a population of 10,000 of these fish living in a lake; so N = 10,000 individuals—but you don’t know this! • You capture 250 of fish and mark them in some way so that you will know if you catch them again in the future; so M = 250 fish, and the proportion of marked individuals in the population is • But you don’t know this, either!! • Now imagine you allow those marked fish to mix in with the population again, and then you capture another batch. This time you catch 360 fish; so C = 360 fish. • Based on the ratio of M to N (0.025), how many of those 360 individuals would you expect to be “recaptures”—i.e., fish that you marked in the first capture?
Using mark-recapture sampling to estimate animal populations where, N = population M = number of individuals marked in initial trapping C = number of individuals captured in census trapping R = number of marked individuals recaptured in census trapping
Using mark-recapture sampling to estimate animal populations • After rearranging to solve for N, this becomes: • Example: • Imagine you capture and mark 150 fish in a lake. (This must be a random, representative sample.) • You release them back into the lake, allowing enough time for them to remix with the population. • You then trap another 220 fish, of which 25 are recaptures (i.e., marked from the initial trapping). • What is your estimate of the total population of fish in the lake?