1. The side-blotched lizard, Uta stansburiana, stretches from central Washington State in the north to parts of Mexico in the south. Although all the populations throughout this range constitute one species, populations in the north and south differ in life history features, showing clinal variation in life history traits. Chapter 11 Life History Strategy

2. Guppy

3. Small populations can be found in relative isolation occupying freshwater pools separated by waterfalls and rapids. In some pools, male guppies sport prominent secondary sexual characteristics: bright body colors and enlarged tail fins in other pools, males are drab, lacking these particular secondary sexual characteristics. Laboratory and field experiments show the reason why---predators.

5. Raised in a greenhouse Predators were added; other were kept predator- free; brightly colored were drab. Drab guppies were transplanted to predator-free pools; after two years were now colorful 所屬網頁 http://www.g-hoener.de/nll.htmhttp://www.g-hoener.de/nll.htm

6. Male guppies, evolution of color varieties After several generations, guppies raised in low- and high-predation environments evolve different features. As measured by the number of bright, conspicuous spots, males become more brightly colored (low predation) or drab (high predation).

7. The bright characteristics certainly draw the intended favorable attention of females. Unfortunately, bright males ate picked off by predators more often than drab males, Overall, fitness results from an overall trade-off between the advantageous (mating success) and disadvantageous consequences (attract predators) of bright, showy guppy color.

8. In some natural pools, guppies are large, reproduce later in life, but produce only small broods of young. In other pools, the guppies are small, reproduce at a young age, but produce large broods of young. Guppies possess the ability to adjust their phenotype by simple physiological or behavioral alteration; ??? Phenotypic plasticity. By quantifying the similarities of relatives, scientists established that the differences in traits were heritable, not just physiological adjustments.

9. Prior field observations noted that guppies are eaten by at least two different fish predators. The killifish, a small predator that preys mainly on small, young guppies. The pike-cichlid, a large predator, that preys mainly on large guppies. When it is present, most mature guppies are small. 所屬網頁 http://www.aiconline.it/spaziosoci/foto/http://www.aiconline.it/spaziosoci/foto/ 所屬網頁 http://www.nmu.edu/biology/Jill/http://www.nmu.edu/biology/Jill/

10. Table 11.2 Guppies

11. When the researchers returned (about 11 years later), the life history of the transplanted guppies had changed. Under predation ……. The transplanted guppies came from pools where the pike-cichlid was present; were transplanted into pools with killifish but no guppies were present prior to the transplant.

12. How the trade-offs are made between body size reproductive age, and brood size depends upon environmental conditions.

13. Time and Energy Budgets

14. 所屬網頁 http://stevenround-birdphotography.com/http://stevenround-birdphotography.com/ Foraging Resting Territorial Abiotic Factors

15. To meet different climatic demands, the rock pipit is likely making simple behavioral adjustments in its allotments of time and energy to various competing activities. 所屬網頁 http://www.homepages.mcb.net/http://www.homepages.mcb.net/ 所屬網頁 http://stevenround-birdphotography.com/http://stevenround-birdphotography.com/

16. The swift, a swallow-like bird, is a “determinate” layer. This means that the number of eggs a female lays is preset and fixed; she does not lay additional eggs if some are lost. In contrast, the familiar barnyard chicken is an “indeterminate” layer. When a laying hen returns to find her clutch size reduced, she lays more to replace the missing eggs.

17. The fixed number of eggs laid is set by her genotype. Some females lay just two eggs, others just three eggs per clutch Three eggs instead of two would get more of their genotype into the next generation; but this has not happened. From year to year, conditions varied, favoring one or the other life history characteristic--clutch size-- in different years.

18. Table 11.4 Swifts

19. One conceivable adaptive strategy of attacked plants might be to increase seed toxicity and thwart the beetles. That beetles evolve, too, producing detoxifying systems to neutralize seed toxins. In attacked plants, individual seeds are small, but in large numbers, chemical defense is reduced; vegetative growth is low. In plants free of attack, individual seeds are large, but fewer; chemical defenses are in place; vegetative growth is high Biotic Factors

21. Which of these two strategies returns the greatest survival benefits depends on how the gains and losses balance out. Depends upon local environmental conditions. Where beetle attack, the beans allocating more energy to reproduction fare better, although at the cost of growth and chemical defense.