Human behavioral ecology (HBE) or human evolutionary ecology applies the principles of

evolutionary theory Evolution is the change in the heritable characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certai ...

and

optimization Mathematical optimization (alternatively spelled ''optimisation'') or mathematical programming is the selection of a best element, with regard to some criteria, from some set of available alternatives. It is generally divided into two subfiel ...

to the study of

human behavior Human behavior is the potential and expressed capacity (Energy (psychological), mentally, Physical activity, physically, and Social action, socially) of human individuals or groups to respond to internal and external Stimulation, stimuli throu ...

al and

cultural diversity Cultural diversity is the quality of diverse or different cultures, as opposed to Monoculturalism, monoculture. It has a variety of meanings in different contexts, sometimes applying to cultural products like art works in museums or entertainment ...

. HBE examines the adaptive design of traits,

behaviors Behavior (American English) or behaviour (British English) is the range of actions of individuals, organisms, systems or artificial entities in some environment. These systems can include other systems or organisms as well as the inanimate ph ...

, and life histories of humans in an

ecological Ecology () is the natural science of the relationships among living organisms and their environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere levels. Ecology overlaps with the closely re ...

context. One aim of modern human behavioral ecology is to determine how ecological and

social Social organisms, including human(s), live collectively in interacting populations. This interaction is considered social whether they are aware of it or not, and whether the exchange is voluntary or not. Etymology The word "social" derives fro ...

factors influence and shape behavioral flexibility within and between human

populations Population is a set of humans or other organisms in a given region or area. Governments conduct a census to quantify the resident population size within a given jurisdiction. The term is also applied to non-human animals, microorganisms, and pl ...

. Among other things, HBE attempts to explain variation in human behavior as adaptive solutions to the competing life-history demands of growth, development,

reproduction Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. There are two forms of reproduction: Asexual reproduction, asexual and Sexual ...

, parental care, and mate acquisition. HBE overlaps with

evolutionary psychology Evolutionary psychology is a theoretical approach in psychology that examines cognition and behavior from a modern evolutionary perspective. It seeks to identify human psychological adaptations with regard to the ancestral problems they evolved ...

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

cultural ecology Cultural ecology is the study of human adaptations to social and physical environments. Human adaptation refers to both biological and cultural processes that enable a population to survive and reproduce within a given or changing environment. Th ...

, and

decision theory Decision theory or the theory of rational choice is a branch of probability theory, probability, economics, and analytic philosophy that uses expected utility and probabilities, probability to model how individuals would behave Rationality, ratio ...

. It is most prominent in disciplines such as

anthropology Anthropology is the scientific study of humanity, concerned with human behavior, human biology, cultures, society, societies, and linguistics, in both the present and past, including archaic humans. Social anthropology studies patterns of behav ...

and

psychology Psychology is the scientific study of mind and behavior. Its subject matter includes the behavior of humans and nonhumans, both consciousness, conscious and Unconscious mind, unconscious phenomena, and mental processes such as thoughts, feel ...

where

human evolution ''Homo sapiens'' is a distinct species of the hominid family of primates, which also includes all the great apes. Over their evolutionary history, humans gradually developed traits such as Human skeletal changes due to bipedalism, bipedalism, de ...

is considered relevant for a holistic understanding of

Evolutionary theory

Human behavioral ecology rests upon a foundation of evolutionary theory. This includes aspects of both general evolutionary theory and established middle-level evolutionary theories, as well. Aspects of general evolutionary theory include: *

Natural selection Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the Heredity, heritable traits characteristic of a population over generation ...

, the process by which individual

organism An organism is any life, living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Many criteria, few of them widely accepted, have be ...

s with favorable

traits Trait may refer to: * Phenotypic trait in biology, which involve genes and characteristics of organisms * Genotypic trait, sometimes but not always presenting as a phenotypic trait * Personality, traits that predict an individual's behavior. ** ...

are more likely to survive and

reproduce Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. There are two forms of reproduction: asexual and sexual. In asexual reprod ...

. *

Sexual selection Sexual selection is a mechanism of evolution in which members of one sex mate choice, choose mates of the other sex to mating, mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex ...

, the

theory A theory is a systematic and rational form of abstract thinking about a phenomenon, or the conclusions derived from such thinking. It involves contemplative and logical reasoning, often supported by processes such as observation, experimentation, ...

that competition for mates between individuals of the same sex results in differential mating and reproduction. *

Kin selection Kin selection is a process whereby natural selection favours a trait due to its positive effects on the reproductive success of an organism's relatives, even when at a cost to the organism's own survival and reproduction. Kin selection can lead ...

, the changes in

gene frequency In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

across generations that are driven at least in part by interactions between related individuals. *

Inclusive fitness Inclusive fitness is a conceptual framework in evolutionary biology first defined by W. D. Hamilton in 1964. It is primarily used to aid the understanding of how social traits are expected to evolve in structured populations. It involves partit ...

, the sum of an individual's own reproductive success, (natural and sexual selection), plus the effects the individual's actions have on the reproductive success of that individual's kin, (kin selection). Middle-level evolutionary theories used in HBE include: *The theory of

parental investment Parental investment, in evolutionary biology and evolutionary psychology, is any parental expenditure (e.g. time, energy, resources) that benefits offspring.Clutton-Brock, T.H. 1991. ''The Evolution of Parental Care''. Princeton, NJ: Princeton ...

, which predicts that the sex making the largest investment in

lactation Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process naturally occurs with all sexually mature female mammals, although it may predate mammals. The process ...

, nurturing and protecting

offspring In biology, offspring are the young creation of living organisms, produced either by sexual reproduction, sexual or asexual reproduction. Collective offspring may be known as a brood or progeny. This can refer to a set of simultaneous offspring ...

will be more discriminating in mating and that the sex that invests less in offspring will compete for access to the higher investing sex. *

Parent–offspring conflict Parent–offspring conflict (POC) is an expression coined in 1974 by Robert Trivers. It is used to describe the evolutionary conflict arising from differences in optimal parental investment (PI) in an offspring from the standpoint of the parent an ...

, which predicts that because the genetic interests of parents and offspring are not identical, offspring will be selected to manipulate their parents in order to ensure higher investment, and that, conversely, parents will be selected to manipulate their offspring. *The theory of

reciprocal altruism In evolutionary biology, reciprocal altruism is a behaviour whereby an organism acts in a manner that temporarily reduces its fitness while increasing another organism's fitness, with the expectation that the other organism will act in a similar m ...

, a form of

altruism Altruism is the concern for the well-being of others, independently of personal benefit or reciprocity. The word ''altruism'' was popularised (and possibly coined) by the French philosopher Auguste Comte in French, as , for an antonym of egoi ...

in which one organism provides a benefit to another in the expectation of future reciprocation. *The

Trivers–Willard hypothesis In evolutionary biology and evolutionary psychology, the Trivers–Willard hypothesis, formally proposed by Robert Trivers and Dan Willard in 1973, suggests that female mammals adjust the sex ratio of offspring in response to maternal condition, ...

, which proposes that parents should invest more in the sex that gives them the greatest reproductive payoff (grandchildren) with increasing or marginal investment. *

r/K selection theory In ecology, selection theory relates to the selection of combinations of traits in an organism that trade off between quantity and quality of offspring. The focus on either an increased quantity of offspring at the expense of reduced individua ...

, which, in

ecology Ecology () is the natural science of the relationships among living organisms and their Natural environment, environment. Ecology considers organisms at the individual, population, community (ecology), community, ecosystem, and biosphere lev ...

, relates to the selection of traits in organisms that allow success in particular environments.

r-selected In ecology, selection theory relates to the selection of combinations of traits in an organism that trade off between quantity and quality of offspring. The focus on either an increased quantity of offspring at the expense of reduced individua ...

species – in unstable or unpredictable environments – produce many offspring, any individual one of which is unlikely to survive to adulthood, while

K-selected In ecology, selection theory relates to the natural selection, selection of combinations of Trait (biological), traits in an organism that trade off between quantity and quality of offspring. The focus on either an increased quantity of offsprin ...

species – in stable or predictable environments – invest more heavily in fewer offspring, each of which has a better chance of surviving to adulthood. *

Evolutionary game theory Evolutionary game theory (EGT) is the application of game theory to evolving populations in biology. It defines a framework of contests, strategies, and analytics into which Darwinism, Darwinian competition can be modelled. It originated in 1973 wi ...

, the application of

population genetics Population genetics is a subfield of genetics that deals with genetic differences within and among populations, and is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as Adaptation (biology), adaptation, s ...

-inspired models of change in gene frequency in populations to

game theory Game theory is the study of mathematical models of strategic interactions. It has applications in many fields of social science, and is used extensively in economics, logic, systems science and computer science. Initially, game theory addressed ...

. *

Evolutionarily stable strategy An evolutionarily stable strategy (ESS) is a strategy (or set of strategies) that is ''impermeable'' when adopted by a population in adaptation to a specific environment, that is to say it cannot be displaced by an alternative strategy (or set of ...

, which refers to a

strategy Strategy (from Greek στρατηγία ''stratēgia'', "troop leadership; office of general, command, generalship") is a general plan to achieve one or more long-term or overall goals under conditions of uncertainty. In the sense of the " a ...

, which if adopted by a population, cannot be invaded by any competing alternative strategy.

Basic principles

Methodology

As a subdiscipline of ecology, HBE draws upon systemic and

individualistic Individualism is the moral stance, political philosophy, ideology, and social outlook that emphasizes the intrinsic worth of the individual. Individualists promote realizing one's goals and desires, valuing independence and self-reliance, and a ...

frameworks in studying human relational patterns. Breaking down complex socioecological patterns into their structural-functional relationships allows scientists to describe social behaviour from the perspective of the overall ecosystem rather than isolated agents. An example of the research methodology in practice might see a scientist examining marriage rates by taking into account local options, cultural preferences, socioeconomic status, political freedoms, and so forth.

Ecological selectionism

Ecological selectionism refers to the assumption that humans are highly flexible in their behaviors. Furthermore, it assumes that various ecological forces select for various behaviors that optimize humans' inclusive fitness in their given ecological context.

Conditional strategies

Human behavioral ecologists assume that what might be the most adaptive strategy in one environment might not be the most adaptive strategy in another environment. Conditional strategies, therefore, can be represented in the following statement: *In environmental context X, engage in adaptive strategy A. *In environmental context Y, engage in adaptive strategy B.

Phenotypic gambit

The phenotypic gambit refers to the simplifying assumption that

complex traits Complex traits are phenotypes that are controlled by two or more genes and do not follow Mendel's Law of Dominance. They may have a range of expression which is typically continuous. Both environmental and genetic factors often impact the variat ...

, such as behavioural traits, can be modelled as if they were controlled by single distinct alleles, representing alternate strategies. In other words, the phenotypic gambit assumes that "selection will favour traits with high fitness ...irrespective of the particulars of inheritance."

Modeling

Theoretical models that human behavioral ecologists employ include, but are not limited to: *

Optimal foraging theory Optimal foraging theory (OFT) is a behavioral ecology model that helps predict how an animal behaves when searching for food. Although obtaining food provides the animal with energy, searching for and capturing the food require both energy and ti ...

, which states that organisms focus on consuming the most energy while expending the least amount of energy. *

Life history theory Life history theory (LHT) is an analytical frameworkVitzthum, V. (2008). Evolutionary models of women's reproductive functioning. ''Annual Review of Anthropology'', ''37'', 53-73 designed to study the diversity of life history strategies used by d ...

, which postulates that many of the

physiological Physiology (; ) is the science, scientific study of function (biology), functions and mechanism (biology), mechanisms in a life, living system. As a branches of science, subdiscipline of biology, physiology focuses on how organisms, organ syst ...

traits and behaviors of individuals may be best understood in relation to the key maturational and reproductive characteristics that define the life course. * Sex allocation theory, which predicts that parents should bias their reproductive investments toward the offspring sex generating the greatest fitness return. *The

polygyny threshold model The polygyny threshold model is an evolutionary explanation of polygyny, the mating of one male of a species with more than one female. The model shows how females may gain a higher level of biological fitness by mating with a male who already has ...

, which suggests that

polygyny Polygyny () is a form of polygamy entailing the marriage of a man to several women. The term polygyny is from Neoclassical Greek πολυγυνία (); . Incidence Polygyny is more widespread in Africa than in any other continent. Some scholar ...

is driven by female choice of mates who control more resources relative to other potential mates in the population.

References

External links

The Human Behavioral Ecology Bibliography
– Maintained by Kermyt G. Anderson Demography Anthropology Behavioral ecology Behavioural sciences H Sociobiology