![Twilight_description_full_day](https://upload.wikimedia.org/wikipedia/commons/d/d1/Twilight_description_full_day.svg)
Matutinal, matinal (in
entomological
Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as arach ...
writings),
and matutine are terms used in the
life sciences
This list of life sciences comprises the branches of science that involve the scientific study of life – such as microorganisms, plants, and animals including human beings. This science is one of the two major branches of natural science, the ...
to indicate something of, relating to, or occurring in the early
morning
Morning is the period from sunrise to noon. There are no exact times for when morning begins (also true of evening and night) because it can vary according to one's lifestyle and the hours of daylight at each time of year. However, morning strict ...
. The term may describe
crepuscular animal
In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal, vespertine, or both. This is distinguished from diurnal and nocturnal behavior, where an animal is active during the hours of dayligh ...
s that are significantly active during the pre
dawn
Dawn is the time that marks the beginning of twilight before sunrise. It is recognized by the appearance of indirect sunlight being scattered in Earth's atmosphere, when the centre of the Sun's disc has reached 18° below the observer's horizo ...
or early morning hours. During the morning
twilight
Twilight is light produced by sunlight scattering in the upper atmosphere, when the Sun is below the horizon, which illuminates the lower atmosphere and the Earth's surface. The word twilight can also refer to the periods of time when this il ...
period and shortly thereafter, these animals partake in important tasks, such as scanning for mates,
mating
In biology, mating is the pairing of either opposite-sex or hermaphroditic organisms for the purposes of sexual reproduction. ''Fertilization'' is the fusion of two gametes. ''Copulation'' is the union of the sex organs of two sexually reproduc ...
, and
foraging
Foraging is searching for wild food resources. It affects an animal's Fitness (biology), fitness because it plays an important role in an animal's ability to survive and reproduce. Optimal foraging theory, Foraging theory is a branch of behaviora ...
.
Matutinal behaviour is thought to be
adaptive
Adaptation, in biology, is the process or trait by which organisms or population better match their environment
Adaptation may also refer to:
Arts
* Adaptation (arts), a transfer of a work of art from one medium to another
** Film adaptation, a ...
because there may be less competition between species, and sometimes even a higher prevalence of food during these hours.
It may also serve as an
anti-predator adaptation
Anti-predator adaptations are mechanisms developed through evolution that assist prey organisms in their constant struggle against predators. Throughout the animal kingdom, adaptations have evolved for every stage of this struggle, namely by avo ...
by allowing animals to sit between the brink of danger that may come with
nocturnal
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
and
diurnal activity.
Etymology
The word ''matutinal'' is derived from the
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
word ', meaning "of or pertaining to the morning", from ''
Mātūta'', the Roman goddess of the morning or dawn (+ ''-īnus'' '-ine' + ''-ālis'' '-al').
Adaptive relevance
Selection pressures
Any cause that reduces or increases reproductive success in a portion of a population potentially exerts evolutionary pressure, selective pressure or selection pressure, driving natural selection. It is a quantitative description of the amount of ...
, such as high predatory activity or low food may require animals to change their behaviours to adapt. An animal changing the time of day at which it carries out significant tasks (e.g., mating and/or foraging) is recognized as one of these adaptive behaviours. For example, human activity, which is more predominant during daylight hours, has forced certain species (most often larger mammals) living in
urban area
An urban area, built-up area or urban agglomeration is a human settlement with a high population density and infrastructure of built environment. Urban areas are created through urbanization and are categorized by urban morphology as cities, t ...
s to shift their schedules to crepuscular ones.
When observed in environments where there is little or no human activity, these same species often do not exhibit this temporal shift.
It may be argued that if the goal is to avoid human activity, or any other diurnal predator's activity, a nocturnal schedule would be safer. However, many of these animals depend on sight, so a matutinal or crepuscular schedule is especially advantageous as it allows animals to both avoid predation, and have sufficient light to mate and forage.
Matutinal mating
For certain species, commencing mating during the early morning's twilight period may be adaptive because it could reduce the risk of predation, increase the chance of finding mates, and reduce competition for mates, all of which may increase reproductive success.
Anti-predatory adaptation
Animals are generally more vulnerable during
copulation
Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetrat ...
(e.g., praying mantis), so mating during a time when there is less predatory activity may be an anti-predatory adaptation.
Some species may even take up to several hours to finish mating, which increases this vulnerability.
For species that copulate for longer periods, shifting their mating schedule may additionally allow enough time for the male to completely inseminate the female (i.e., it will reduce the chance of having to escape from a predator mid-copulation). One example of a matutinal mating routine is exhibited by female
tropical praying mantises (''Mantis religiosa).''
To avoid detection from predators they use different stances to
blend in with their environment. They can orient themselves to look like leaves or sticks. However, when females are ready to mate they will take up a different posture where they expose
pheromone
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavio ...
-emitting
gland
In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland).
Structure
De ...
s that attract mates, and in the process must disengage from their normal camouflaging stance. Likely to compensate for this vulnerability, females will initiate this stance only at first light when diurnal predators that are visual hunters are less active (e.g., birds and insectivorous primates).
Reduced competition
![Superb_Fairywren](https://upload.wikimedia.org/wikipedia/commons/4/4b/Superb_Fairywren.jpg)
Some animals engage in matutinal searching flights to find mates early in the morning. It is thought that this is adaptive because it increases the chance of finding mates, and reduces competition for mates (i.e., by flying directly to a potential mate before it has a chance to find other mates). This is supported by the mating behaviour of certain
socially monogamous
Monogamy ( ) is a form of dyadic relationship in which an individual has only one partner during their lifetime. Alternately, only one partner at any one time (serial monogamy) — as compared to the various forms of non-monogamy (e.g., polyga ...
birds. For example, female
superb fairywren
The superb fairywren (''Malurus cyaneus'') is a passerine bird in the Australasian wren family, Maluridae, and is common and familiar across south-eastern Australia. It is a sedentary and territorial species, also exhibiting a high degree of se ...
s (''Malurus cyaneus)'', are a monogamous bird that perform
extra-pair copulation
Extra-pair copulation (EPC) is a mating behaviour in monogamous species. Monogamy is the practice of having only one sexual partner at any one time, forming a long-term bond and combining efforts to raise offspring together; mating outside this pai ...
s during matutinal hours.
One explanation for the prevalence of extra-pair copulation is that it enhances the
gene pool
The gene pool is the set of all genes, or genetic information, in any population, usually of a particular species.
Description
A large gene pool indicates extensive genetic diversity, which is associated with robust populations that can surv ...
of the species' offspring.
This activity is most often seen matutinally because they: (1) can avoid being followed by their monogamous partner in the dimly-lit early morning, (2) males are more likely to be present in their territory during these hours, and (3) males are more likely to have a higher quantity of sperm in the early morning.
These points may apply to how matutinal mating is adaptive in other species.
Similar behaviours have been observed in other species, such as in males of two species of
dragonflies
A dragonfly is a flying insect belonging to the infraorder Anisoptera below the order Odonata. About 3,000 extant species of true dragonfly are known. Most are tropical, with fewer species in temperate regions. Loss of wetland habitat threa ...
(''Aeshna grandis'' & ''Aeshna viridis'').
They engage in matutinal searching flights each morning until they find a receptive female to mate with. A similar phenomenon is seen in male praying mantises, where they respond to the emerging light each morning by increasing flight activity.
Matutinal foraging
Some animals exhibit increased foraging behaviour during the matutinal hours. Some examples of why this may be adaptive are: (1) it may increase predatory success and (2) competition for food may be reduced.
Predatory adaptation
The
blue shark
The blue shark (''Prionace glauca''), also known as the great blue shark, is a species of requiem shark, in the family Carcharhinidae, which inhabits deep waters in the world's temperate and tropical oceans. Averaging around and preferring co ...
(''Prionace glauca)'' is a predator that primarily hunts during the pre-dawn to dawn period.
During matutinal hours, they spend more time than any other point in the day at the surface of the ocean.
It is likely that they are taking advantage of the increased density of prey at the water's surface during dawn.
It is also possible that, since only a thin layer at the surface of the ocean is dimly lit during this twilight period, the shark (coming up from the dark ocean depths) has vision of the prey, but the prey do not have vision of the shark, allowing the shark to sneak up on the prey, increasing predatory success.
Reduced competition
Some bees (e.g., ''Ptiloglossa arizonensis, Pt. jonesi, Caupolicana,'' and ''Hemihalictus lustrans'') forage matutinally, possibly because there is less competition for food during this period.
The ''Hemihalictus lustrans,'' for example, is a bee that works mutualistically with the dandelion ''Pyrrhopappus carolinianus'' during matutinal hours''.''
''Pyrrhopappus carolinianus'' flowers very early in the morning and ''Hemihalictus lustrans'' begins foraging at the same time. The bee tears open the dandelion's anthers just as it is flowering, which speeds up
anthesis
Anthesis is the period during which a flower is fully open and functional. It may also refer to the onset of that period.
The onset of anthesis is spectacular in some species. In ''Banksia'' species, for example, anthesis involves the extension ...
and ensures that it almost always has first claim to the dandelion's pollen.
Physiological evidence of adaptation
These matutinal behaviours may be induced by physiological adaptations. Robinson & Robinson
reversed the day-night schedule of female tropical praying mantises (i.e., by placing them in light during the night, and in a chamber with no light during the day). After they adjusted to the schedule, the praying mantises were removed from their chambers at different times throughout the newly adjusted night period and placed in the light. Each praying mantis initiated their pheromone-emitting stance during this transition regardless of the time, which suggests that this behaviour depends solely on the transition from dark to light. The authors suggested that this was likely a physiological adaptation.
See also
*
Crepuscular animal
In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal, vespertine, or both. This is distinguished from diurnal and nocturnal behavior, where an animal is active during the hours of dayligh ...
*
Vespertine (biology)
Vespertine is a term used in the life sciences to indicate something of, relating to, or occurring in the evening. In botany, a vespertine flower is one that opens or blooms in the evening. In zoology, the term is used for a creature that beco ...
*
Diurnality
Diurnality is a form of plant and ethology, animal behavior characterized by activity during daytime, with a period of sleeping or other inactivity at night. The common adjective used for daytime activity is "diurnal". The timing of activity by a ...
*
Nocturnality
Nocturnality is an animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite.
Nocturnal creatures generally have highly developed sens ...
*
Crypsis
In ecology, crypsis is the ability of an animal or a plant to avoid observation or detection by other animals. It may be a predation strategy or an antipredator adaptation. Methods include camouflage, nocturnality, subterranean lifestyle and ...
References
{{Light Ethology
Ethology