Evolution And Ecology Of The Organism

by Rose, Michael R.; Mueller, Laurence D.

• ISBN13: 9780130104045
• ISBN10: 0130104043
• Format: Hardcover
• Copyright: 2006-01-01
• Publisher: PRENTICE

Summary

For sophomore- to junior-level courses in Evolution, with an Introductory Biology prerequisite.This text introduces biology majors to the basic concepts of the fields comprising Darwinian biology: population genetics, population ecology, community ecology, macroevolution, physiological ecology, systematics, and functional morphology. The general theme is the interconnectedness of organism, environment, and evolution. Just as biochemistry and molecular biology provide the foundation for our understanding of the cell, evolutionary biology and ecology are used to construct a foundation for understanding the organism. Using evocative language and an eye-catching magazine format, the authors aim to prepare undergraduates for more advanced specialist courses in Darwinian biology as they pursue their degrees.

Table of Contents

PART ONE INTRODUCTION TO DARWINIAN BIOLOGY
Darwin, Ecology, and Evolution	3	(40)
Darwin's Life	4	(12)
There are many Darwin myths, perhaps because Darwin had an impact on the general culture	4	(2)
Darwin grew up an intellectually curious, but unemployed, member of the English landed gentry	6	(2)
On the voyage of the Beagle, Darwin learned a lot of biology, but he did not discover evolution	8	(2)
Darwin intuited evolution from the differences between birds from the Galapagos Islands	10	(2)
Darwin developed the concept of natural selection to explain the direction of evolutionary change	12	(2)
Despite publishing the Origin of Species, Darwin was a much-honored scientist during his life	14	(2)
Darwin's Ecology and Evolution	16	(5)
Darwin used ecology to create evolutionary biology	16	(2)
Malthus's essay led Darwin to apply ecology to other problems of evolutionary biology	18	(1)
Artificial selection allowed Darwin to develop the concept of evolution by natural selection further	19	(1)
To support his theory Darwin used the fossil record, but regarded it as highly imperfect	20	(1)
Darwin needed Mendel	21	(3)
Evolution requires the inheritance of variation	21	(1)
Darwin tried to explain the mechanism of inheritance using his theory of pangenesis, but failed	22	(1)
Mendel solved the problem of inheritance, but it took time for Mendel's genetics to join with Darwinism	23	(1)
The Birth of Modern Ecology	24	(6)
Predator-prey cycles and the origins of theoretical ecology	24	(2)
The idea of competitive exclusion and the birth of experimental ecology	26	(2)
The controversy between density-dependent and density-independent population regulation	28	(2)
Darwin's View of Life	30	(13)
Darwin's theories broke with prevailing biological doctrines, which were theological and vitalist in their foundations	30	(1)
Darwin's evolution was materialistic, unlike some other evolutionary theories	31	(1)
Natural selection supplies direction to Darwin's evolution, but is not itself directed	32	(2)
Ecology and natural selection combine in Darwin's theory to produce inefficient and historically contingent evolution	34	(2)
Darwin argued that all order in the history of life was a result of evolution by natural selection	36	(2)
The Darwinian universe and the organisms within it undergo materially important change	38	(2)
Despite great need, it took a long time for biology to be transformed by the Darwinian revolution	40	(3)
Evolutionary Trees in the Ecological Garden	43	(33)
The Tree Concept	44	(8)
The history of life could have followed a variety of patterns, including an absence of evolution	44	(2)
Lyell's system of life allowed many origins of species and many extinctions, but no evolution	46	(1)
The only figure in the Origin of Species was an evolutionary tree	47	(1)
Modern evolutionary trees represent species as growing, splitting, and truncated branches	48	(2)
Evolutionary trees are often built using maximum parsimony	50	(2)
Some Important Trees	52	(6)
The origin of life and the three domains	52	(2)
Eukaryotic life evolved from endosymbiosis	54	(2)
The trees of prokaryotic life	56	(1)
The trees of eukaryotic life	57	(1)
Using Trees to Study Evolution	58	(8)
The classification of species can be explained elegantly with Darwin's evolutionary tree concept	58	(2)
Fossil differentiation often follows tree patterns	60	(2)
Biogeographic patterns can be explained in terms of geology, migration, and evolutionary history	62	(2)
Developmental patterns can be explained using evolutionary trees	64	(2)
The Comparative Method	66	(10)
The comparative method uses the pattern of adaptation among species and their environments to infer the evolutionary causes of particular adaptations	66	(2)
Evolutionary trees can be used to test hypotheses of adaptation objectively	68	(2)
Homology: When similar features among related species are inherited from their common ancestor	70	(2)
Homoplasy: Parallel patterns in evolution that are due to natural selection, not ancestry	72	(4)
PART TWO MACHINERY OF EVOLUTION	76	(152)
The Genetic Engine	79	(46)
How Genetics Works	80	(6)
Genetics is central to modern biology	80	(2)
Reproduction may transmit one or two copies of the hereditary information to the next generation	82	(2)
Sexual reproduction recombines chromosomes containing many discrete loci	84	(2)
Genes in Populations	86	(6)
Genes specify phenotypes, then the phenotypes are selected, which changes gene frequencies	86	(2)
The evolutionary state of a population is defined by its genotype frequencies	88	(1)
With no selection, allele frequencies do not change in randomly mating large populations	89	(1)
When the alleles of different loci are combined randomly, they are in linkage equilibrium	90	(2)
Quantitative Characters	92	(8)
Quantitative characters have to be studied statistically	92	(2)
When environmental (E) and genetic (G) influences on a phenotype (P) are independent, VP = VG + VE	94	(2)
The genes that make up a genotype may determine the phenotype additively or nonadditively	96	(2)
The resemblance of relatives is determined by the ratio of the additive genetic variance to the phenotypic variance	98	(2)
Sex and Recombination	100	(6)
Population genetics is like shuffling and dealing cards	100	(2)
With random mating, sex-chromosome genes that start out at different frequencies move toward the same frequency	102	(2)
Recombination progressively breaks up nonrandom associations of alleles among loci	104	(2)
Inbreeding	106	(12)
Inbreeding is a bad thing in normally outbreeding natural populations	106	(2)
The degree of inbreeding can be calculated from the probability that parents share alleles from a common ancestor	108	(2)
When relatives mate regularly, homozygotes increase in frequency while heterozygotes decrease in frequency	110	(2)
Inbreeding tends to reduce the variance of quantitative characters within inbred lines	112	(2)
Inbreeding tends to reduce the average value of beneficial characters	114	(2)
Inbreeding can arise from the subdivision of populations	116	(2)
Genetic Drift	118	(7)
Genetics is like card games, and genetic drift is like a trip to Las Vegas	118	(2)
Populations can undergo evolutionary change from genetic drift alone	120	(2)
Genetic drift can lead to the loss or fixation of alleles	122	(3)
Natural Selection	125	(40)
Darwin and Natural Selection	126	(6)
Darwin did not expect to observe natural selection	126	(2)
Darwin's original theory of natural selection made nature, through the struggle for existence, the breeder or selector	128	(1)
The workings of selection are evident in the procedures of artificial selection	129	(1)
Multiple generations of artificial selection can change a character substantially	130	(2)
The Cycle of Natural Selection	132	(6)
Natural selection will sometimes have more impact than artificial selection, sometimes less	132	(2)
Natural selection requires genetic variation for characters related to fitness	134	(1)
Natural selection changes the patterns of survival and reproduction of organisms undergoing selection	135	(1)
With selectable genetic variation, natural selection changes the gene frequencies and phenotypes of the next generation	136	(2)
Phenotypic Patterns of Natural Selection	138	(6)
Natural selection acts powerfully on just a few characters at a time	138	(2)
Directional selection favors organisms with phenotypes that are at one extreme relative to the average phenotype	140	(1)
Stabilizing selection favors organisms that have intermediate characteristics	141	(1)
Disruptive selection favors organisms that have character values at both extremes of the phenotypic distribution	142	(2)
Genetic Mechanisms of Natural Selection	144	(8)
Genetics complicates the action of natural selection	144	(2)
Selection in asexual populations increases mean fitness until the genetic variance in fitness is used up	146	(1)
When heterozygotes are intermediate, selection with sex is similar to selection without sex	147	(1)
Selection with recurring mutation prevents the achievement of maximum fitness	148	(2)
When heterozygotes are superior, selection maintains genetic variation	150	(1)
Selection in favor of rare genotypes can also maintain genetic variability	151	(1)
Natural Selection in the Laboratory	152	(6)
Natural selection in the laboratory offers a view of what is possible in evolution	152	(2)
Bacterial evolution in the laboratory shows that the response to selection is very powerful at first, but tends to slow down	154	(2)
Laboratory experiments show that sexual populations can respond quickly to intense directional selection	156	(2)
Natural Selection in the Wild	158	(7)
The evolution of antibiotics illustrates the basic principles of natural selection in the wild	158	(2)
The best documented example of long-term natural selection in the wild is industrial melanism	160	(1)
Selection for increased beak size occurred in Darwin's finches on the Galapagos Islands	161	(1)
Human sickle-cell anemia is maintained by heterozy-gote superiority	162	(3)
Molecular Evolution	165	(22)
Genes and Genomes	166	(8)
The genome is not a huge library of information	166	(2)
The eukaryotic gene is a complex structure with many nucleotides that do not code for amino acids	168	(2)
Transposable elements are mobile genes that make copies of themselves to move about the genome	170	(2)
Tandem arrays of genes increase and decrease gene number by unequal crossing over	172	(1)
Prokaryotic genomes are concatenations of genes with occasional inserted sequences, while eukaryotic genomes have large intergenic regions that play no apparent role in gene replication or function	173	(1)
Neutral Molecular Evolution	174	(6)
The neutral theory of molecular evolution is based on genetic drift	174	(2)
The molecular clock is based on the observation that the rate of molecular evolution is roughly constant	176	(2)
Unlike nonsynonymous substitutions, synonymous substitutions proceed at a fairly uniform rate across a wide range of DNA sequences	178	(2)
Selective Molecular Evolution	180	(7)
Natural selection eliminates, substitutes, and maintains specific molecular genetic variants	180	(1)
It is uncertain how much nucleotide evolution is due to selection, but there is some evidence for selection on particular nucleotides	181	(1)
Genes that have been duplicated by reverse transcription may degenerate or evolve new functions	182	(2)
Genome size is highly variable, perhaps due to the proliferation of useless elements	184	(3)
Speciation and Extinction	187	(41)
Allopatric Speciation	188	(8)
The biological species concept is based on the reproductive isolation of organisms that are given the opportunity to mate	188	(2)
Species may be isolated by a failure to reproduce that occurs after fertilization, which will select for isolation before fertilization	190	(2)
Geographical separation of populations fosters speciation	192	(2)
The genetic mechanisms of allopatric speciation may be adaptive or nonadaptive	194	(2)
Sympatric Speciation	196	(8)
Sympatric speciation is difficult because of a lack of evolutionary isolation among groups	196	(2)
Polyploidization can produce instant sympatric speciation	198	(2)
Host-race differentiation might cause sympatric speciation	200	(2)
Laboratory experiments show the feasibility of host-race sympatric speciation	202	(2)
Hybridization	204	(4)
Hybridization sometimes occurs in nature	204	(2)
Hybridization can produce polyploidization and instant speciation	206	(2)
Species Radiations	208	(4)
The Cambrian explosion was a spectacular radiation of animal species	208	(2)
The colonization of the Galapagos Archipelago by finches led to an adaptive radiation	210	(2)
Punctuated Equilibrium	212	(4)
Mayr's speciation model implies punctuated equilibrium	212	(2)
Hopeful monsters can escape evolutionary stasis, in theory	214	(2)
Retail Extinction	216	(6)
Extinctions destroy unique products of biological evolution	216	(2)
Normal biotic diversity is the result of a balance between the processes of speciation and extinction	218	(2)
Species that escape extinction tend to disperse widely over large geographic ranges	220	(2)
Mass Extinction	222	(6)
Mass extinctions have intermittently eliminated a large proportion of living species	222	(2)
The mass extinctions probably arose from large-body impacts	224	(4)
PART THREE THE DARWINIAN ORGANISM	228	(120)
Life History of the Organism	231	(24)
Fitness and Life Histories	232	(9)
There are many types of life history	232	(2)
The fitness of semelparous organisms is the product of viability and fecundity	234	(1)
Iteroparous organisms have age-structured life histories	235	(1)
Populations with age structure can grow exponentially according to a stable age-distribution	236	(2)
In iteroparous organisms, fitness can be calculated from estimates of population growth rates	238	(2)
A small increase in semelparous fecundity may be favored over iteroparity	240	(1)
Trade-Offs in Life-History Evolution	241	(5)
When evolution increases one life-history character, another life-history character may decrease	241	(1)
Trade-offs between survival and reproduction may lead to the evolution of reproductive restraint	242	(2)
Trade-offs between offspring size and offspring survival lead to the evolution of intermediate size	244	(2)
Evolution of Aging	246	(9)
Aging has been studied from very different perspectives, including evolutionary biology	246	(2)
The survival and fertility of iteroparous plants and animals change with age	248	(2)
The force of natural selection acting on survival falls with adult age	250	(1)
Aging should not evolve in fissile organisms, but it should in life cycles without vegetative reproduction	251	(1)
Changing the force of natural selection can produce rapid evolution of aging patterns	252	(3)
Physical Ecology of the Organism	255	(16)
Temperature and Light	256	(8)
Animals regulate their temperature in a variety of ways	256	(1)
Temperature profoundly influences organismal function	257	(1)
The temperature coefficient, Q10, is used to express the effect of temperature on organismal function	258	(2)
Life at extreme temperatures reveals how organisms adapt to environmental stress	260	(2)
The physical properties of light striking the Earth constitute a key environmental factor mediating the physiology, distribution, and abundance of organisms	262	(2)
The Size and Shape of Organisms	264	(7)
The surface area to volume ratio of an organism affects its interaction with the environment	264	(2)
Changes in size have a major effect on organismal structure and function	266	(2)
Allometric methods are used to quantify changes in form and function associated with size	268	(3)
How Organisms Work	271	(26)
Chemical Transport	272	(10)
Whole organisms must cope with regulating solutes, gases, and water	272	(1)
Mechanisms of osmoregulation vary with environment due to distinct physical properties of air and water	273	(1)
Countercurrent exchange is used to control gas, heat, and ion flux	274	(2)
The uptake of oxygen by animals is accomplished by gills, lungs, and occasionally skin	276	(2)
Transport of water in plants uses transpiration and the physical properties of water	278	(2)
Animals transport fluids using specialized circulatory systems	280	(2)
Evolution of Physiological Systems	282	(6)
Desiccation is a major problem for terrestrial life	282	(2)
The ability to tolerate nitrogen wastes is molded by natural selection	284	(2)
Fat is beautiful when episodes of starvation are a predictable part of life	286	(2)
Energy Production and Utilization	288	(9)
Many factors affect energy production and utilization	288	(2)
Metabolic rates are determined by a variety of factors	290	(2)
The ``cost of transport'' is a key metric of the energetic expense of moving in motile organisms	292	(2)
Energy is the basis of trade-offs for the evolution of many traits	294	(3)
Balancing Birth and Death	297	(32)
The Population Bomb	298	(6)
Populations are collections of interbreeding individuals and the basic units of ecology and evolution	298	(2)
Populations may grow exponentially for short periods of time	300	(2)
In crowded populations, survival and fertility decline	302	(2)
Space is the important limiting resource for some populations	304	(1)
Malthusian Specters	304	(8)
Experimental and theoretical ecology begin with investigations of single-species population growth	304	(2)
Density-regulated populations do not grow without bound	306	(2)
Density-regulated populations may exhibit chaotic behavior	308	(2)
Many organisms have complex life cycles that are density-regulated	310	(2)
Density-Dependent Natural Selection	312	(8)
The early theories of r- and K-selection were verbal	312	(2)
Great differences exist within species in their ability to tolerate crowding	314	(1)
Natural selection will increase rates of population growth	315	(1)
Natural selection often cannot increase population growth rates at high and low density simultaneously	316	(2)
The stability of populations is affected by the environment, but not selection	318	(2)
The Bomb Didn't Blow	320	(9)
A combination of increased food production and changes in demographic patterns have helped humans avert Malthusian catastrophes	320	(2)
Forecasting trends in human populations relies on knowledge of human birth and death patterns	322	(2)
The use of selection and genetic engineering vastly expanded agricultural productivity---though their long-term ecological effects are not known	324	(2)
Humans began to restrict their reproduction	326	(3)
Dispersal	329	(19)
Dispersal and Migration	330	(7)
Migration and dispersal have a variety of important genetic and ecological consequences	330	(2)
A population may consist of many small populations linked by migration	332	(1)
Home-range size is related to energetic requirements	333	(1)
The dispersal of many marine organisms is mediated by ocean currents	334	(2)
Plant morphology affects the efficiency of passive dispersal	336	(1)
Dormancy	337	(5)
Some species escape bad conditions by ``travelling'' through time: dormancy	337	(1)
Plant seeds are some of the longest-lasting dormant life-cycle stages	338	(2)
Many animals and plants survive in seasonal climates through the use of dormancy	340	(1)
Many organisms have neither long-term nor seasonal dormancy, but show intermittent dormancy	341	(1)
Consequences of Dispersal	342	(6)
Novel ecological structures: metapopulations	342	(2)
Connecting the genetics of populations: gene flow	344	(4)
PART FOUR ECOLOGY OF INTERACTING SPECIES	348	(180)
Competition	351	(30)
The Ecological and Evolutionary Process of Competition	352	(10)
Plants and animals compete for resources	352	(2)
Competition for resources between individuals affects fitness	354	(2)
Plant competition for limited resources may lead to stable coexistence	356	(2)
Belowground plant structures compete for microorganisms, water, and essential nutrients	358	(2)
Intraspecific competitive ability responds to natural selection	360	(2)
The Consequences of Competition	362	(8)
Gause developed his competitive exclusion principle from experiments with Paramecium	362	(2)
Interspecific competition affects population dynamics	364	(2)
The Lotka-Volterra model of competition predicts competitive exclusion or stable coexistence	366	(2)
Competition affects the distribution of species	368	(2)
The Ecological Niche	370	(11)
Several ecologists contributed to the development of the ecological niche concept	370	(2)
Determination of the realized niche can reveal how different species avoid competition	372	(2)
The number of species that exist in a particular environment may be determined by competition	374	(2)
Important morphological or behavioral traits may evolve, reducing levels of competition between species in a process called character displacement	376	(5)
Predation	381	(24)
Predator-Prey Dynamics	382	(6)
The dynamics of predator-prey populations are intimately connected	382	(2)
The Lotka-Volterra model of predator-prey dynamics predicts cycles, although for reasons which probably do not apply to natural populations	384	(2)
More realistic models incorporate density-dependent prey dynamics and predator satiation	386	(2)
How to be a Predator	388	(6)
A variety of factors determine how predators forage	388	(2)
Foragers may optimize energy gain per unit of time, or minimize time spent foraging	390	(1)
The behavior of foraging animals often conforms to simple predictions	391	(1)
Central-place foragers should recover more food the farther they travel	392	(2)
How to Avoid Becoming Prey	394	(4)
The process of prey capture can be broken down into many stages	394	(2)
Prey may avoid predators by being difficult to find	396	(1)
Prey may avoid predators by looking like other distasteful species	397	(1)
Plant-Herbivore Interactions	398	(7)
Plants show immediate and long-term reactions to herbivory	398	(2)
Herbivores employ various strategies to overcome plant defenses	400	(5)
Parasitism and Mutualism	405	(32)
Parasite-Host Interactions	406	(10)
The specialized life cycle of parasites makes them useful for controlling certain pest species	406	(2)
Parasitoids cannot be too effective at finding hosts if they are to avoid extinction	408	(2)
Parasites are often very specialized in their feeding habits and life cycles, to match their hosts	410	(2)
As hosts evolve genetic resistance to parasites, the parasites evolve means of overcoming this resistance	412	(2)
The coevolution of hosts and parasites also depends on ecological factors	414	(2)
Mutualistic Interactions	416	(14)
Mutualisms may provide several benefits to participating species, including nutrition, protection, and transportation	416	(2)
Mutualisms may involve the reciprocal exchange of essential nutrients	418	(2)
Mutualisms may involve the transportation of individuals or gametes	420	(2)
Mutualism may involve the provision of protection from predators or competitors	422	(2)
Mutualisms often evolve as a direct consequence of negative interactions between two or more species	424	(2)
The evolution of mutualisms should be facilitated when the reproduction of host and symbiont coincides	426	(2)
Levels of antagonism between hosts and parasites may depend on the frequency of opportunities for horizontal transfer	428	(2)
The Coevolutionary Process	430	(7)
Coevolution is a complex process that may depend on selection, migration, and genetic drift	430	(2)
Host-parasite phylogenies reveal common histories of speciation	432	(2)
Coevolution of bacteria and eukaryotic hosts shows little switching between pathogenic and mutualistic lifestyles	434	(3)
Communities and Ecosystems	437	(38)
Energy Flow	438	(6)
The flow of energy is a central organizing theme in community ecology	438	(2)
In most biological communities, all energy comes from the sun	440	(2)
The efficiency of energy transfer from one trophic level to the next varies among communities	442	(2)
Equilibrium and Nonequilibrium Communities	444	(6)
Community stability can be disrupted by sudden changes in the physical environment	444	(2)
The diversity of species in a community may depend on environmental disturbance	446	(1)
The number of species on islands represents a balance between extinction and immigration	447	(1)
Habitats go through predictable changes in species composition over time	448	(2)
Community Organization	450	(14)
The diversity of a community may be affected by competition, predation, or primary productivity	450	(2)
The number of species in a community may depend on predation	452	(2)
River communities show a top-down structure	454	(2)
Many features of food webs can be described by the cascade model	456	(2)
Food-web chain length is proportional to ecosystem size in lakes	458	(2)
Increased productivity can increase food-chain length but decrease stability	460	(2)
The structure of communities is also affected by the genetic structure of its members	462	(2)
Ecosystems	464	(11)
An important feature of ecosystems and their biological communities is their interaction with the physical environment	464	(2)
Essential nutrients are recycled through biological systems	466	(2)
Soil carbon levels are affected by temperature	468	(2)
Species diversity affects ecosystem performance	470	(5)
The Biosphere and the Physical Environment	475	(32)
Global Climates	476	(10)
Global climates are not static, but show major cycles every 100,000 years	476	(2)
The sun's energy and air currents are responsible for rain forests and deserts	478	(2)
The tilt of the Earth on its axis results in seasonal cycles in temperature and daylight	480	(2)
The ocean currents modify land climates	482	(2)
Atmospheric CO2 and water vapor trap much of the sun's energy by a process called the greenhouse effect	484	(2)
Local Climates	486	(6)
Many factors may affect local climates	486	(2)
Local topography may affect climate: Rain-shadow deserts	488	(2)
The biological community may affect the climate	490	(2)
The Ecology and Evolution of Biomes	492	(8)
The ocean biomes cover 70 percent of the Earth's surface	492	(2)
The physical properties of water have important consequences for life in freshwater lakes and ponds	494	(2)
Adaptations to reduce water loss characterize the plant and animal life found in deserts	496	(2)
Forests are important terrestrial biomes often characterized by their dominant tree species	498	(2)
Global Change	500	(7)
Human activities can quickly cause global environmental change	500	(2)
Human activities add gases to our atmosphere, leading to acid rain and ozone depletion	502	(2)
Human agricultural practices have increased the spread of deserts	504	(3)
Conservation	507	(21)
Basics of Conservation	508	(12)
Conservation biology requires an understanding of the genetics, ecology, and physiology of managed populations	508	(2)
Ecological principles can be used to design reserves	510	(2)
The loss of habitat and habitat fragmentation leads to species extinctions	512	(2)
The last century has been marked by the loss of terrestrial forests and the acceleration of species extinctions	514	(2)
Ecological theory can be used to guide harvesting from natural populations	516	(2)
Risk assessment	518	(2)
Applications	520	(8)
Application of conservation biology include designing reserves, reducing species extinctions, and managing exotic populations	520	(2)
Human activity has led to the extinction of many species in recent history	522	(2)
Some of the most prominent endangered species live in terrestrial ecosystems	524	(2)
Introduced exotic species often require management	526	(2)
PART FIVE DARWINIAN BIOLOGY IN EVERYDAY LIFE	528	(135)
Evolution and Ecology of Sex	531	(26)
Why Is Sex a Problem?	532	(6)
Many species do not have sex	532	(2)
There is a two-fold fitness cost to producing sons	534	(2)
Sex requires sexual anatomy and exposure to predators or venereal diseases	536	(1)
Sex breaks up successful genotypes	537	(1)
Is Sex a Good Thing Despite Its Problems?	538	(12)
Sex cannot be explained by evolutionary history	538	(2)
With moderately frequent beneficial mutations, sex can speed up the rate of adaptation	540	(2)
Sex may reduce competition between siblings, increasing the fitness of sexual parents	542	(2)
Sex may generate variability required for hosts to evolve faster than their diseases and parasites	544	(2)
Sex may help get rid of deleterious mutations over the entire genome	546	(2)
Sex may be maintained because newly asexual females have depressed fitness	548	(2)
Origin of Sex	550	(7)
The origin of sex is even more complicated than its maintenance	550	(2)
Simple forms of sex can originate from mobile genetic elements	552	(2)
Recombination may have evolved as a by-product of selection for DNA repair	554	(3)
Mating Strategies	557	(18)
Gametes and Sexes	558	(3)
Most sexual animals have two types of gamete: Sperm and eggs	558	(1)
Unbiased sex ratios are normally favored by natural selection	559	(1)
The hymenopteran sex ratio system is often used to bias sex ratios when mating is incestuous	560	(1)
Which Sex Should You Be?	561	(7)
Separate sexes evolve when it is hard to combine male and female sexual functions	561	(1)
The evolution of hermaphrodites also depends on the genetics of self-fertilization and the reproductive ecology of mating	562	(2)
Male and female roles can be reversed	564	(2)
Some species switch from one sex to another in order to increase fertility	566	(2)
How Many Partners?	568	(7)
There are three main mating patterns: Promiscuous, monogamous, and polygamous	568	(2)
Sexual selection favors individuals that are sexually attractive, combative, or territorial	570	(2)
The incubator is selected to find sexually attractive and helpful mates	572	(3)
Social Evolution	575	(26)
Group Selection	576	(6)
Biological altruism is critical for social evolution	576	(1)
Group selection can prevail over individual selection	577	(3)
Group selection may be the best explanation for some cases of biological altruism	580	(2)
Kin Selection	582	(6)
Selection can act on families	582	(2)
Altruism toward relatives is favored when the cost is less than the benefit times relatedness	584	(1)
Insects with closely related sisters evolve complex social systems dominated by females	585	(1)
Kin selection led to the evolution of the burrowing societies of termites and naked mole rats	586	(2)
Evolutionary Games	588	(13)
Animals balance aggression and peaceful behavior as if social interaction were a game	588	(2)
Fitness depends on strategies that specify an animal's behavior in its conflicts	590	(2)
Violent behavior is rare if the costs of injury are greater than the benefits of victory	592	(2)
Natural selection may favor the Retaliator strategy, which is peaceful unless attacked	594	(2)
Bourgeois settles conflict using ownership	596	(5)
Human Evolution and Human Behavior	601	(30)
The Hominid Phylogeny	602	(7)
Humans evolved from Old World apes, which split from the rest of the primates about 20 million years ago	602	(2)
Chimpanzees are our closest living relatives, followed by gorillas	604	(2)
There were at least two major upright hominid lineages, which may have included multiple species each	606	(2)
Human evolution featured expansion of the brain-case, reduction in the jaws, and changes to the rest of the skeleton	608	(1)
Human Population Genetics	609	(9)
Molecular genetic tools are crucial to unraveling the patterns of human evolution	609	(1)
Genetic evidence suggests that the Neanderthals belonged to a different species from the lineage that was ancestral to modern humans	610	(2)
There are two main theories concerning the ancestry of modern human populations	612	(2)
The latest data strongly support recent African proliferation of modern humans	614	(2)
Modern human populations seem to be a patchwork of local differentiation, with little racial differentiation	616	(2)
Why Did Evolution Produce Humans?	618	(6)
The puzzle of our evolution has generated both intellectual aversion and gratuitous speculation	618	(1)
Humans must have evolved by intense directional selection for abilities derived from increased brain sizes	619	(1)
The hypothesis that we were selected only to use technology is undermined by the material simplicity of some cultures relative to their social complexity	620	(2)
The hypothesis that we were selected only for social calculation is undermined by our facility with complex material technologies	622	(1)
Human evolution probably involved a combination of selection pressures favoring both technology and social behavior	623	(1)
Human Behavior from an Evolutionary Perspective	624	(7)
There is a long tradition of Darwinian analysis of human behavior, despite controversy about it	624	(2)
Some human behavior can be analyzed by the same methods used to study animal behavior	626	(1)
Human behavior may be organized to Darwinian ends without genetic specification, perhaps unconsciously	627	(4)
Darwinian Medicine	631	(32)
Human Imperfection	632	(8)
Some of our medical problems arise from our evolutionary history	632	(2)
Genetic diseases are extreme forms of human imperfection generated by rare genotypes	634	(2)
From an evolutionary perspective, germline engineering has significant technological limitations	636	(2)
Somatic engineering is less problematic than germline engineering	638	(2)
Contagious Disease	640	(10)
Human diseases are shaped by long-term evolution and global ecology	640	(2)
Some of our body's responses to contagious disease are beneficial: Vomiting is good for you	642	(2)
The evolution of pathogen virulence depends on the ecology of infection	644	(2)
Resistance to antibiotics has evolved in bacteria, requiring the development of new antibiotics	646	(2)
HIV illustrates the importance of rapid virus evolution in medicine	648	(2)
Aging	650	(5)
Evolution and genetics offer new hope for the medical treatment of the elderly	650	(2)
Humans live so long due to patterns of selection	652	(2)
Postponement of human aging will be achieved by combining evolutionary and other biotechnologies	654	(1)
Brain Disorders	655	(8)
Not all ``mental illness'' is pathological	655	(1)
Schizophrenia is an example of a Darwinian brain disorder	656	(2)
It is unclear whether all affect disorders are actively sustained by natural selection	658	(2)
The sociopath combines subjective well-being with pathological Darwinian outcomes	660	(3)
STATISTICAL APPENDICES	663	(6)
Appendix A Random variables and the rules of probability	663	(2)
Appendix B Statistical distributions and correlation	665	(2)
Appendix C Linear regression and the analysis of variance	667	(2)
Glossary	669	(8)
Bibliography	677	(4)
Photo Credits	681	(4)
Index	685