Reproductive and Somatic Effort in Dogwoods. What is life history?. Grasses. Trees. vs. fast growth. slow growth. quick repro. delayed repro. An organism’s typical pattern of : Growth & Survival Reproduction. Components of Life History. SOMATIC effort E for growth/survival.
Reproductive and Somatic Effort in Dogwoods
Components of Life History
All organisms have limited energy; they allocate some energy to somatic effort & some to reproductive effort
somatic & reproductive effort = trade-off
Theory 1. Phenotypic plasticity
Theory 2. Sunlight affects reproductive effort
Theory 3. Age affects reproduction
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 37.
2) Measure the DBH (cm) of each tree trunk.
Bark: dark brown with squarish, scaly blocks.
Young trees will be smooth and not as distinctive.
Examples of different numbers of bud scales
Dogwood with two bud scales. Twigs are slender, green or purple.
Opposite leaf scars
Dogwood leaf scars are opposite, small, and encircle twig.
Example of alternate leaf scars
Fruit: bright red, in clusters (late summer, fall)
Flowers: white, four petals (spring)
Leaves: opposite, veins curved