Tinbergen's four questions

Reconstructing the phylogeny of a species often makes it possible to understand the "uniqueness" of recent characteristics: Earlier phylogenetic stages and (pre-) conditions which persist often also determine the form of more modern characteristics. For instance, the vertebrate eye (including the human eye) has a blind spot, whereas octopus eyes do not. In those two lineages, the eye was originally constructed one way or the other. Once the vertebrate eye was constructed, there were no intermediate forms that were both adaptive and would have enabled it to evolve without a blind spot.

It corresponds to Aristotle's

• The brain: For example, Broca's area, a small section of the human brain, has a critical role in linguistic capability.
• Hormones: Chemicals used to communicate among cells of an individual organism. Testosterone
  , for instance, stimulates aggressive behaviour in a number of species.
• Pheromones
  : Chemicals used to communicate among members of the same species. Some species (e.g., dogs and some moths) use pheromones to attract mates.

Ontogeny is the process of development of an individual organism from the zygote through the embryo to the adult form.

In the latter half of the twentieth century, social scientists debated whether human behaviour was the product of nature (genes) or nurture (environment in the developmental period, including culture).

An example of interaction (as distinct from the sum of the components) involves familiarity from childhood. In a number of species, individuals prefer to associate with familiar individuals but prefer to mate with unfamiliar ones (Alcock 2001:85–89, Incest taboo, Incest). By inference, genes affecting living together interact with the environment differently from genes affecting mating behaviour. A simple example of interaction involves plants: Some plants grow toward the light (phototropism) and some away from gravity (gravitropism).

Many forms of developmental learning have a

A related concept is labeled "biased learning" (Alcock 2001:101–103) and "prepared learning" (Wilson, 1998:86–87). For instance, after eating food that subsequently made them sick, rats are predisposed to associate that food with smell, not sound (Alcock 2001:101–103). Many primate species learn to fear snakes with little experience (Wilson, 1998:86–87).[7]

See developmental biology and developmental psychology.

It corresponds to Aristotle's

Four ways of explaining visual perception:

• Function: To find food and avoid danger.
• Phylogeny: The vertebrate eye initially developed with a blind spot, but the lack of adaptive intermediate forms prevented the loss of the blind spot.
• Causation: The lens of the eye focuses light on the retina.
• Development:
  Neurons need the stimulation of light
  to wire the eye to the brain (Moore, 2001:98–99).

Four ways of explaining the Westermarck effect, the lack of sexual interest in one's siblings (Wilson, 1998:189–196):

• Function: To discourage inbreeding, which decreases the number of viable offspring.
• Phylogeny: Found in a number of mammalian species, suggesting initial evolution tens of millions of years ago.
• Mechanism: Little is known about the neuromechanism.
• Ontogeny: Results from familiarity with another individual early in life, especially in the first 30 months for humans. The effect is manifested in nonrelatives raised together, for instance, in kibbutzs.

Romantic love

Four ways of explaining romantic love have been used to provide a comprehensive biological definition (Bode & Kushnick, 2021):^[8]

• Function: Mate choice, courtship, sex, pair-bonding.
• Phylogeny: Evolved by co-opting mother-infant bonding mechanisms sometime in the recent evolutionary history of humans.
• Mechanisms: Social, psychological mate choice, genetic, neurobiological, and endocrinological mechanisms cause romantic love.
• Ontogeny: Romantic love can first manifest in childhood, manifests with all its characteristics following puberty, but can manifest across the lifespan.

Sleep

Sleep has been described using Tinbergen's four questions as a framework (Bode & Kuula, 2021):^[9]

• Function: Energy restoration, metabolic regulation, thermoregulation, boosting immune system, detoxification, brain maturation, circuit reorganization, synaptic optimization, avoiding danger.
• Phylogeny: Sleep exists in invertebrates, lower vertebrates, and higher vertebrates. NREM and REM sleep exist in eutheria, marsupialiformes, and also evolved in birds.
• Mechanisms: Mechanisms regulate wakefulness, sleep onset, and sleep. Specific mechanisms involve neurotransmitters, genes, neural structures, and the circadian rhythm.
• Ontogeny: Sleep manifests differently in babies, infants, children, adolescents, adults, and older adults. Differences include the stages of sleep, sleep duration, and sex differences.

Use of the four-question schema as "periodic table"

Konrad Lorenz, Julian Huxley and Niko Tinbergen were familiar with both conceptual categories (i.e. the central questions of biological research: 1. - 4. and the levels of inquiry: a. - g.), the tabulation was made by Gerhard Medicus.^[10] The tabulated schema is used as the central organizing device in many animal behaviour, ethology, behavioural ecology and evolutionary psychology textbooks (e.g., Alcock, 2001) . One advantage of this organizational system, what might be called the "periodic table of life sciences," is that it highlights gaps in knowledge, analogous to the role played by the periodic table of elements in the early years of chemistry.

This "