Table 1 Glossary of technical terms used in this article

Autocorrelation

A statistical association between environmental states across space or time. Positive temporal autocorrelation implies that conditions at one point in time are similar to those in the near future.

Bayesian updating

A method for revising a belief about the world in the light of new evidence, based on Bayes's rule. See Appendix A (additional file 1) for more details.

Estimate

A probability distribution for possible states of the world, based on the information available to an individual from its past experiences and evolutionary history. Note that no cognitive process, conscious or otherwise, is implied.

Cue

An experience that potentially provides information about environmental conditions. Note that cues can be uninformative, unreliable or even misleading (cf. information, which by definition is always informative).

Information

A reduction in uncertainty (about the state of the world).

Informativeness

The extent to which a cue reduces uncertainty.

Mutual information

The amount by which uncertainty is reduced (by observation of a new cue).

Plasticity

The degree to which cues received during development affect an organism's phenotype. Here we include both activational (or contextual) plasticity, whereby the organism immediately adjusts its phenotype in response to current cues, and narrow-sense developmental plasticity, in which there is a lasting phenotypic response to cues received in the past [21–23].

Posterior

In Bayesian updating, a revised estimate of the state of the world after new evidence has been taken into account.

Prior

In Bayesian updating, an initial estimate of the state of the world before new evidence is taken into account.

Reliability

The extent to which a cue indicates the true state of the world (either now or in the future).

Sensitive window

A developmental period or stage in which experience shapes phenotypic development to a larger extent than in other periods or stages. This definition encompasses both sensitive periods—in which plasticity is a function of chronological age—and sensitive stages—in which plasticity is not tied to a specific age but is a function of the organism's developmental stage, which can depend on its previous experiences (e.g. the duration of a sensitive window might depend on the consistency of experiences earlier in development [35]).

Uncertainty

The probabilistic nature of an organism's knowledge about the world, determined by factors beyond its immediate control but potentially reducible by sampling [94].

Value of information

The change in expected future reproductive success associated with a reduction in uncertainty. Note that this is always non-negative: information, once received, never reduces fitness [41].