REPRODUCTIVE BEHAVIORS: MEANING, PAIRING, DISPLAYS, EFFECT OF DISPLAYS, TERROTORIALITY, SEASONAL MIGRATION, POLLINATION IN PLANTS, TYPES, FEATURES, AGENTS, DIFFERENCES

These are behaviors adapted by many organisms, mammals, insects, plants and other reproductive agents in replicating same species of same parents. This is usually employed by organisms to reproduce same kinds of themselves thereby adding to the teeming population.

These reproductive behaviors is a result of courtship behaviors, pairing, displays, territoriality, and finally mating of copulating organisms. The reason for reproduction is that new same species are introduced into the population before the parent organisms dies.

COURTSHIP BEHAVIOR IN ANIMALS

Courtship behaviours consists of instinctive behaviour in response to certain external stimulus. These behaviours is carried out in sequence and alternatively performed by male and female organisms. Each step acts as a stimulus for the next sequence or step. It may involve territorial defence, displays, singing, and pairing. Examples are seen in some birds, fishes and animals.

When courtship behaviour coincides with heat or ovulation or reproduction period, mating occurs which leads to the release of gametes and hence increases the chances of fertilization.

PAIRING
Male and female animals leave the fold and follow one another. This pairing may often be preceded by some mating signs. An example of this is a male toad or frog going into the pond and start croaking while the female follows in response. Pairing also occurs in birds, winged termites and mammals.

DISPLAYS
Displays are special attractive features or behaviour exhibited by some males to lure the females into mating. Courtship behaviours are found in peacocks, turkeys, pigeon, red head of male Agama Lizard and domestic fowls.

HOW DISPLAY IN ANIMALS AFFECT THE REPRODUCTION PROCESS
1. It’s used to attract males and female organisms.
2. It stimulates the organism sexually or often induces ovulation in some animals.
3. It ensures that ovulation and mating are done.
4. In animal breeding, it indicates that the animals are on heat.

TERRITORIALITY
Territoriality is a behaviour of a group to acquire an area for living, breeding, and defending it against other members of the same species. Examples are Agama Lizard, robin, etc.

EFFECTS OF REPRODUCTION PROCESSES IN ANIMALS
1. Often times, a mature male establishes a territory from which other rivals are driven away.
2. Courtship displays are carried out within the territory.
3. Mating also takes place in this actively defended territory.
4. Security is provided for the young within the territory.
5. Territories enhances the transmission of desirable traits/ qualities in a population.

SEASONAL MIGRATION

Seasonal migration is the movement of some animals that live in one habitat to a more suitable place or environment at a particular season where there is need for reproduction or breeding. Examples of these are found in fishes (salmon, herrings, and eels) and birds (kites).

POLLINATION IN PLANTS
Pollination is the transfer of pollen grains from the anther to the stigma of a flower. This allows for species to be pollinated within a population. Examples of these pollinating agents are animals, wind, man, water, etc.

There are two main types of pollination which are highlighted below;
1. SELF POLLINATION: It is the transfer of mature pollen grains from the anther to the stigma of the same flower. Examples of these are Cotton, Guinea Grass, Pea and Tomato.
2. CROSS POLLINATION: It is the transfer of the pollen grain from the anther to the stigma of another flower of the same species. Examples are; Morning Glory, Hibiscus, and Flamboyant Flower.

FEATURE OF SELF POLLINATED FLOWER
1. Both the anther and the stigma of a bisexual flower ripen at the same time and the situation is described as Homogany.
2. The stamen and pistil of some flowers are enclosed in the corolla that never open and such condition is described as Cleistogamy.
3. Anthers may be situated above the stigmas.
4. Filaments are longer than style and can recoil.

FEATURES OF CROSS POLLINATED FLOWERS
1. The flowers are Protandrous that is the anthers mature before the stigma
2. The stigma of a flower matures earlier than its pollen grain
3. The flowers is always unisexual. That is the male and female flowers are borne by different plants
4. Some may be self- sterile. That is the pollen grains will not germinate on a stigma of the same flower.
The agents of pollination are insects, wind, water, and other animals.

CHARACTERISTICS OF INSECT POLLINATED FLOWERS
1. Large and brightly coloured corolla attracts insects
2. They are often scented
3. They secrete nectar
4. Pollen grains are rough and sticky to adhere to bodies of insects
5. Stigmas are sticky so that pollen grains can adhere strongly on them. Examples are Crotalaria, Sun flower, Pride of Barbados, and Bougainvillea.

CHARACTERISTICS OF WIND POLLINATED FLOWERS
1. Flowers are not brightly coloured, with no scent and no nectar.
2. Stigmas are feathery, exposing large surface area to wind.
3. Stigmas hang out to expose itself to pollen grains in the wind.
4. Anthers shed large quantities of pollen to increase chances of pollination by the wind.
5. Filaments are elongated to expose protruding anthers to the wind.
6. Pollen grains are light, easily carried by the wind.
7. Filaments can shake in the slightest of wind to release pollen grains to the wind. Examples are Guinea Grass and Maize.

DIFFERENCES BETWEEN INSECT AND WIND POLLINATED FLOWERS
1. Insect pollinated flowers have large sizes and they are scented while wind pollinated flowers have small sizes and they are not scented.
2. In insect pollinated flowers, their stigmas are flat or lobed with sticky surfaces for easy adherence of pollen grains while wind pollinated flower stigmas are large and feathery hanging outside the flower providing large area for easy trapping of pollens.
3. In insect pollinated flowers, the stamen produces sticky or spiky pollen grains for easy adherence to the stigma while in wind pollinated flowers, its powdery and smooth pollen grin, light for easy transportation.
4. In insect pollinated flower, the anther contain few pollen grains while in wind pollinated flower, the anther contain large quantity of pollen grains to allow for wastage.
5. In insect pollinated flowers, nectary gland is present while the nectary gland is absent in wind pollinated flowers.
6. The shape and floral parts are such as to enable insects get dusted, with pollen grains during visiting in insect pollinated flowers, while in wind pollinated flowers, there is no particular adaptive shape, flowers are small and exposed.

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