Feeding habits

Feeding habit is the method adopted by different organism to carry out their feeding mechanism.

1. Filter feeding/Microphagous:- This is a method of feeding used by some aquatic animal that feed on microscopic organism surrounding them. The microscopic organism are phytoplankton (microscopic plant) and zooplankton (microscopic animal). These two groups of microorganism are referred to as plankton. Example of filter feeders are mosquito larva, duck, prawn and tilapia fish. There are many aquatic animal and they wallow in water through sieve-like structure on their bodies in order to collect large quantity of their prey.
2. Fluid feeding: Is a method of feeding in which some animal feed on fluid substances derived either from animal or plant. If the food is a solid, it has to be converted into liquid form before it is being sucked into the gut. Example of organisms which are fluid feeder are housefly, adult mosquito and butterfly.
3. Wallower: These are organism that rest within or wallow in their food e.g. tape worm which live in the intestine of man, the organism live within the host and absorb digested food directly into it’s entire body surface to absorb digested food from the host
4. Sucker:– These are organism which feed by sucking fluid from plant or animal. They are mainly insects e.g. bug, mosquito, butterfly, aphids and tsetse fly.
5. Saprophytic feeding:- The saprophytes are mainly non-green plant which do not have chloroplast and therefore cannot manufacture their own food. They then feed on dead and decayed organic matter from which they derive their food e.g. Rhizopus, mushroom and mucor. They have the following features:

• They have hyphae or rhizoid instead through which they pour enzymes for digestion.
• They are capable of carrying out extra cellular digestion.
• The digested portion of the organic matter is later re-absorbed into their body by diffusion.

6. Parasitic feeding:- This feeding habit is carried by both plant and animal parasites. A parasite is a small organism that live in or on another large organism called host from which the parasite obtain food without contributing anything in return during which the host is harmed. Example of animal parasite are tick, lice, mite, fleas which are called ecto-parasites while tape worm, round worm, guinea worm are example of endo-parasite.

The plant parasites are cassytha, doodler and mistletoe. The plant parasites normally develop a structure called hastorium/hastoria with which they use to absorb nutrient from the host plant.

MODIFICATION AND MECHANISM OF FEEDING IN SOME ANIMALS

(1) Absorbing Mechanism

This mechanism is used by endo-parasites which practise parasitic feeding on their host. It has no mouth, but absorb digested food from the intestine of their host (man). The body of tapeworm  is modified and adapted to parasitic feeding in the following ways:

1. It possess hook and sucker for the attachment to the intestine of their hosts.
2. The body has thick cuticle which protect the organism from being digested by the host enzyme.

• The body of tapeworm is flat to provide large surface area for absorption of digested food.

1. Food is able to penetrate through the body surface.

(2) Biting And Chewing Mechanism

The method is adopted by insects such as grasshopper and cockroach. They have mouth parts for biting and  chewing. These insects have different mouth parts which are modified and adapted for biting and chewing:

1. Labrum:- It is a projecting upper mouth part (upper lips) which prevent food from falling off the mouth while chewing.
2. Labium:- The labium is the lower lips. It is a mouth part formed from a fused pair of appendages. It is used to prevent wastage of food from the mouth.

• Mandible:- It is a pair of lower jaw which form insect mouth parts and is used for biting and cutting food.

1. Maxillae:- The maxillae is a mouth part (two pairs) that is used for breaking down food which the mandibles would have chewed for easy digestion.

(3) Sucking Mechanism

The popular organism that feed in this manner are mosquito, butterfly and housefly. These insects have  different modification of mouth parts for their feeding through sucking.

1. MOSQUITO

(I) Proboscis: – It is a long or tubular mouth part used for feeding, sucking of blood and other purposes.

(II) Stylet: – It is a long appendages. It is used for penetrating the skin in order to open it up and suck blood.

(III) Labium: – (Lower lip) It is a part of mouth  of mosquito adapted for sucking as it can be folded back to allow stylet to function in cutting the skin open.

(IV) The mouth of mosquito can produce saliva which prevents clotting of blood while it is being sucked.

1. BUTTERFLY

Adult butterfly and moths feed mainly on flower nectar and other sugars such as those contained in the sap of wounded trees. The butterfly and moth used their distinctive mouth parts to feed on the nectar of flower. Their mouth is located between the eyes.

(I) Proboscis: – This is a long coiled-tube used for sucking nectar of flower. The insect is capable of recoiling the long proboscis under its head when not in use.

(II) Tasting hair: – Butterflies have hair-like structure on their feet to sense food and it also responsible for tasting the food.

1. HOUSEFLY

The housefly develops mouth parts that are used for specialized feeding on a wide range of materials. Other families of flies are black flies cralflies. Housefly has the following mouth parts:

(I) Proboscis: – Which is applied to wet surface and suck up fluid by means of capillary action.

(II) Labella: – It is used in collaboration with the proboscis to enhance feeding in housefly

(III) Sponging: – It is one of the special feeding mechanisms of the housefly which make  the feeding very easy for the housefly.