PART 4   Ecology and the Environment

14  •  Population Ecology 571

Planet at capacity: patterns of population growth

Population ecology is the study of how populations interact with their environments. 572

14.1

What is ecology? 572

14.2

A population perspective is necessary in ecology. 573

14.3

Populations can grow quickly for a while, but not forever. 574

14.4

A population’s growth is limited by its environment. 576

14.5

Some populations cycle between large and small. 578

14.6

“Maximum sustainable yield” is useful but nearly impossible to implement. 580

A life history is like a species summary. 582

14.7

Life histories are shaped by natural selection. 582

14.8

There are trade-offs between growth, reproduction, and longevity. 584

14.9

This is how we do it: Life history trade-offs: rapid growth comes at a cost. 585

14.10

Populations can be described quantitatively in life tables and survivorship curves. 587

Ecology influences the evolution of aging in a population. 589

14.11

Things fall apart: what is aging and why does it occur? 589

14.12

What determines the average longevity in different species? 592

14.13

Can we slow down the process of aging? 593

The human population is growing rapidly. 595

14.14

Age pyramids reveal much about a population. 595

14.15

As less-developed countries become more developed, a demographic transition often occurs. 597

14.16

Human population growth: how high can it go? 599

StreetBIO: KNOWLEDGE YOU CAN USE

Life history trade-offs and a mini-fountain of youth: what is the relationship between reproduction and longevity? 602