Somatic Effort in Dogwoods What is life history An organisms typical pattern of Growth amp Survival Reproduction Grasses Trees fast growth quick repro slow growth delayed repro ID: 410117
Download Presentation The PPT/PDF document "Reproductive and" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Reproductive and
Somatic Effort
in DogwoodsSlide2
What is life history?
An organism’s typical pattern of :
Growth & Survival
Reproduction
Grasses
Trees
fast growth
quick repro
slow growth
delayed repro
vs.Slide3
All organisms have limited energy; they allocate some energy to somatic effort & some to reproductive effort
s
omatic & reproductive effort = trade-off
Components of Life History
TOTAL ENERGY
SOMATIC effort
E for growth/survival
REPRODUCTIVE effort
E for reproductionSlide4
Purpose
HOW do dogwood trees allocate their energy to SOMATIC and REPRODUCTIVE efforts??
Examine 3 theories on life history trade-off.
SOMATIC
REPROLEAF buds
FLOWER buds
vs.Slide5
Phenotypic Plasticity
A single organism can have >1 phenotype
Depending on environment, 1 tree can have multiple life history patterns
(differences in SOMATIC and REPRO effort
within one tree)Theory 1. Phenotypic plasticitySlide6
Phenotypic Plasticity
Trees with greater annual energy available will have greater reproduction.
Theory
2
. Sunlight affects reproductive effortSlide7
Age & Reproduction
All organisms need time for development before they begin to reproduce (mature)
Theory 3.
Age
affects reproductionSlide8
Field methods
Groups of 4 or 5
Go to either sunny or shady site (as assigned) and survey 20 trees.
1) Record number of leaf buds and flower buds per 40 buds on each tree. If you’re in the roadside environment, you’ll do 20 on the sunny side and 20 on the shady side. Data sheet is on page
63. 2) Measure the DBH (cm) of each tree trunk.Slide9
Dogwood Identification (Winter)
Flower buds
(reproductive)
Leaf bud
(somatic)BothSlide10
Bark: dark brown with squarish, scaly blocks.
Young trees will be smooth and not as distinctive. Slide11
Terminal Buds
Examples of different numbers of bud scales
Dogwood with
two bud scales.
Twigs are slender, green or purple.Slide12
Leaf Scars
Dogwood leaf scars are opposite, small, and encircle twig.
Example of alternate leaf scars
Opposite leaf scars
Terminal budSlide13
Dogwood Identification
Flowers: white, four petals (spring)
Fruit: bright red, in clusters (late summer, fall)
Leaves: opposite, veins curvedSlide14