Where does trait collide?

In personality psychology a trait is a relatively stable, enduring disposition to feel, think, and act in a consistent way across many different situations: extraversion or conscientiousness, for example, is inferred from a pattern of behavior that recurs over time rather than from any single act. Allport's 1966 Traits revisited defended the trait as a real, general readiness for a certain kind of response, and distinguished this lasting disposition from a passing state or mood. The referent is a property of a person's psychological makeup, estimated from ratings and questionnaires, and it is not a heritable feature of an organism, a reusable bundle of code, or a measured property of a plant or animal in its habitat.[1]

Unit

One dimension of personality along which people differ, such as extraversion

Recovery means

Not applicable

Measured by

Operationalised by self-report and observer inventories such as the Big Five, which score a person on each dimension

In genetics a trait is a heritable characteristic or observable feature of an organism, from a single-gene Mendelian character such as seed shape to a quantitative trait such as height that many genes and the environment shape together. Much of the field concerns how the genotype an organism inherits maps onto this observable feature, and Visscher, Hill, and Wray's 2008 review Heritability in the genomics era clarified how the share of trait variation attributable to genetic differences is defined and often misread. The referent is a feature of a living organism that is passed between generations, quantified by heritability and gene mapping, not a behavioral disposition inferred from conduct, a construct in a programming language, or a measure of ecological performance.[2]

Unit

One heritable characteristic of an organism, from a discrete character to a continuous measurement

Recovery means

Not applicable

Measured by

Studied by scoring the characteristic across relatives to estimate its heritability, and by mapping the genes associated with it

In programming language design a trait is a named bundle of methods that can be composed into a class or type to give it behavior, letting the same unit of functionality be reused across otherwise unrelated types without the ambiguities of multiple inheritance. Schärli, Ducasse, Nierstrasz, and Black's 2003 paper Traits: composable units of behaviour introduced the construct and its composition rules, and languages such as Rust, Scala, and PHP later adopted the idea under the same word. The referent is a reusable piece of source code that structures software, defined by the methods it provides, and it has nothing to do with a person's disposition, a heritable feature of an organism, or a measured property in ecology.[3]

Unit

One named set of methods that a type can compose in to gain behavior

Recovery means

Not applicable

Measured by

Defined in source code by the methods it declares and the rules by which it is composed into a type

In trait-based ecology a functional trait is a measurable characteristic of an organism, whether morphological, physiological, or phenological, that influences its performance and ultimately its fitness, such as a plant's leaf area or a seed's mass. Violle, Navas, Vile, and colleagues' 2007 paper Let the concept of trait be functional! argued for a strict definition tied to individual performance, so that traits could be compared across species and used to predict how communities respond to their environment. The referent is a quantified property of an organism scored in the field or laboratory to explain ecological function, distinct from a psychological disposition, an inherited feature named for its transmission, or a bundle of methods in code.[4]

Unit

One measurable characteristic of an organism, scored per individual

Recovery means

Not applicable

Measured by

Quantified per individual by standardised field and laboratory protocols, such as specific leaf area or seed mass