[8] This behaviour is costly in terms of energy and can help explain why the moth has evolved such enhanced visual capabilities for efficient feeding.

The subspecies Deilephila elpenor macromera, found in southern China, northern India, Bhutan and Myanmar, is still regarded as distinct.

The two species are not usually seen together in garden traps because the small elephant hawk moth prefers more open habitats.

Until the 1980s, D. elpenor was only present in the southern half of Scotland, but now it has made its way up the north coast and into the country's mainland as well.

These include rough grassland, heathland, sand dunes, hedgerows, woodland, the open countryside, and even urban gardens.

For example, previous studies on hawk moths have indicated that they can pollinate up to 5–10% of the tree and shrub species in the area they inhabit.

Occasionally, a small number of second generation individuals in a single year will be recorded in the late summer, but this is very rare.

[5] The females lay eggs either singly or in pairs on the leaves of plants that can act as food sources to the caterpillars when they emerge.

Larvae have a backward curving spine or "horn" that is the same colour as their body on the final abdominal segment.

Previous research has shown that the colour variation is not due to a simple inheritance pattern, and specific explanations still remain inconclusive.

Once they have found a secure spot, they will line the pupal chamber with a few strands of silk, pupate, then overwinter as pupae.

They visit flowers and feed on the nectar at night, and are especially attracted to plants such as honeysuckles (Lonicera).

[10] Many Lepidoptera species have evolved eyespots either on their body (when they are caterpillars) or on their wings (as fully grown adults).

This dark, circular marking is generally thought to resemble the eyes of a predator and deter attacks from birds that feed on insects.

[16] Experiments using gas chromatography and mass spectroscopy have identified (E)-11-hexadecenal and (10E, 12E)-10,12-hexadecadienal [(E,E)-bombykal] as the major components of the female sex pheromone.

[17] Most vertebrates, such as humans, lose the ability to use the three types of photoreceptors present in the eye in dim light conditions.

However, all three types of photoreceptors remain functional in various light conditions for D. elpenor, giving it the ability to have scotopic colour vision.

This flight pattern is quite costly; therefore, it is important for the moth to be able to feed effectively by knowing where to find nectar.

[8] Since they are nocturnal, the moths tend to feed on flowers that open or produce nectar at twilight or during the night.

Previous studies have found that fragrance release from the hawkmoth flowers stimulate flower-seeking behaviour by the moths.

Experiments with D. elpenor has shown that it can discriminate between various visual stimuli (i.e. colour) and associate it with a food reward.

This behaviour is especially important because the wrong decision when choosing a food source can prove to be a costly mistake in terms of time and energy resources.

The conspicuous body colouring of certain nocturnal invertebrates, such as the white forehead stripes on the brown huntsman spider, lures the flying moth to its predator.