Unit 3.1-3.3 Ecology PDF

3.1 Specialist vs. Generalist Species Specialists: Smaller range of tolerance, or narrower ecological niche makes them more prone to extinction -Specific food requirements (bamboo) -Less ability to adapt to new conditions Generalists: Larger range of tolerance, broader niche makes them less prone...

3.1 Specialist vs. Generalist Species Specialists: Smaller range of tolerance, or narrower ecological niche makes them more prone to extinction -Specific food requirements (bamboo) -Less ability to adapt to new conditions Generalists: Larger range of tolerance, broader niche makes them less prone to extinction & more likely to be invasive -Broad food req. -High adaptability GENERALIST S VS. SPECIALISTS “ Identify ONE characteristic of specialist species and explain how that characteristic makes them more likely to become extinct than generalist species. 3.2 K-selected & r- selected species Objectives, EKs, and Skills  Quality vs. Quantity R-selected - “quantity” K-selected - “quality” ▰Many offspring, little to no care ▰May reproduce only once ▰Few offspring, heavy parental care to protect them ▻ Ex: insects, fish, plants ▰Usually reproduce many times ▰Shorter lifespan, quick to sexual ▻ Ex: most mammals, birds maturity = high biotic potential = ▰Long lifespan, long time to sexual high pop. growth rate maturity = low biotic potential = ▻ More likely to be invasive slow pop. growth rate ▻ More likely to be disrupted ▻ Better suited for rapidly by env. change or invasives changing env. conditions Traits or characteristics of r-selected & K- selected species It’s a Spectrum Spectrum of Parental Care  Invasive Species & Disturbances R-selected K-selected ▰High biotic potential (rep. rate) = ▰Low biotic potential (rep. rate) = more rapid pop. recovery after hard for pop. to recover after a disturbance disturbance (env. change) ▰Low parental care means death of ▰High parental care means death parent doesn’t impact offspring of parent = death of offspring ▰Not as impacted by invasive species 12 ▰Invasives (usually r) outcompete since their pop. grow quickly for resources with high biotic ▻ More likely to be the invasive potential & rapid pop. growth ▰Larger pop. & faster generation time ▰Less likely to adapt & more likely = higher chance of adaptation & to go extinct lower chance of extinction “ Identify ONE characteristic of an r-selected species that could increase the likelihood of the r- selected species becoming a more successful invasive species than K-selected species Describe the relationship between Zebra Mussel and Unionid Mussel population density in the Hudson River 3.3 Survivorship Curves Objectives, EKs, and Skills  ★ Faster drop in line = quicker die-off of individuals ★ Slower drop in line = longer avg. lifespan Survivorship Curve: line that shows survival rate of a cohort (group of same-aged individuals) in a pop. from birth to death  Type I, II, and III Type I (mostly K-selected) Type III (mostly r-selected) ▰High survivorship early in life ▰High mortality (low survivorship) due to high parental care ▰High survivorship in mid life due early in life due to little to no parental to large size & defensive behavior care ▰Few make it to midlife; slow, steady ▰Rapid decrease in survivorship in late life as old age sets in decline in survivorship in mid life ▰Even fewer make it to adulthood; ▻ Ex: most mammals slow decline in survivorship in old age Type II (in between r & K) ▰Ex: insects, fish, plants ▰Steadilydecreasing survivorship throughout life (coral) 1. What best describes this graph? a. Type I could represent the house mouse, which is an r selected species. b. Type II could be the average of r-selected and K-selected in one specific area. c. Type II could represent elephants, which are typical K-selected species. d. Type II could represent a coral species that  Practice what you know 2. An r-selected species characteristically has a. type I survivorship curve b. few offspring c. a population near carrying capacity d. significant parental care e. a fast population growth rate Describe the trend in survivorship shown in this graph. Justify which type of survivorship curve these data represent.