Ants are social insects of the family Formic and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than 12,500 out of an estimated total of 22,000 species have been classified. They are easily identified by their elbowed antennae and a distinctive node-like structure that forms a slender waist.
Ants form colonies that range in size from a few dozen predatory individuals living in small natural cavities to highly organized colonies which may occupy large territories and consist of millions of individuals. These larger colonies consist mostly of sterile wingless females forming castes of "workers", "soldiers", or other specialized groups. Nearly all ant colonies also have some fertile males called "drones" and one or more fertile females called "queens". The colonies are sometimes described as super organisms because the ants appear to operate as a unified entity, collectively working together to support the colony.
Ants have colonized almost every landmass on Earth. The only places lacking indigenous ants are Antarctica and a few remote or inhospitable islands. Ants thrive in most ecosystems, and may form 15–25% of the terrestrial animal biomass. Their success in so many environments has been attributed to their social organization and their ability to modify habitats, tap resources, and defend themselves. Their long co-evolution with other species has led to mimetic, commensal, parasitic, and mutualistic relationships.
Ant societies have division of labour, communication between individuals, and an ability to solve complex problems. These parallels with human societies have long been an inspiration and subject of study .Many human cultures make use of ants in cuisine, medication and rituals. Some species are valued in their role as biological pest control agents. However, their ability to exploit resources brings ants into conflict with humans, as they can damage crops and invade buildings. Some species, such as the red imported fire ant, are regarded as invasive species, establishing themselves in areas where they are accidentally introduced.
The family Formicidae belongs to the order Hymenoptera, which also includes sawflies, bees and wasps. Ants evolved from a lineage within the vespoid wasps. Phylogenetic analysis suggests that ants arose in the mid-Cretaceous period about 110 to 130 million years ago. After the rise of flowering plants about 100 million years ago they diversified and assumed ecological dominance around 60 million years ago. In 1966, E. O. Wilson and his colleagues identified the fossil remains of an ant (Sphecomyrma freyi) that lived in the Cretaceous period. The specimen, trapped in amber dating back to more than 80 million years ago, has features of both ants and wasps. Sphecomyrma was probably a ground forager but some suggest on the basis of groups such as the Leptanillinae and Martialinae that primitive ants were likely to have been predators underneath the surface of the soil.
During the Cretaceous period, a few species of primitive ants ranged widely on the Laurasian super-continent (the northern hemisphere). They were scarce in comparison to other insects, representing about 1% of the insect population. Ants became dominant after adaptive radiation at the beginning of the Tertiary period. By the Oligocene and Miocene ants had come to represent 20-40% of all insects found in major fossil deposits. Of the species that lived in the Eocene epoch, approximately one in ten genera survive to the present. Genera surviving today comprise 56% of the genera in Baltic amber fossils (early Oligocene), and 92% of the genera in Dominican amber fossils (apparently early Miocene).
Termites, though sometimes called white ants, are not ants and belong to the order Isoptera. Termites are actually more closely related to cockroaches and mantids. Termites are eusocial but differ greatly in the genetics of reproduction. The similar social structure is attributed to convergent evolution. Velvet ants look like large ants, but are wingless female wasps.
Caterpillars
Caterpillars are the larval form of a member of the order Lepidoptera (the insect order comprising butterflies and moths). They are mostly herbivorous in food habit, with some species being insectivorous. Caterpillars are voracious feeders and many of them are considered pests in agriculture. Many moth species are better known in their caterpillar stages because of the damage they cause to fruits and other agricultural produce.Caterpillar hair has been known to be a cause of human health problems. Caterpillar hairs sometimes have venoms in them and species from approximately 12 families of moths or butterflies worldwide can inflict serious human injuries ranging from urticarial dermatitis and atopic asthma to osteochondritis, consumption coagulopathy, renal failure, and intracerebral hemorrhage. Skin rashes are the most common, but there have been fatalities. Lonomia is a frequent cause of envenomation in Brazil, with 354 cases reported between 1989 and 2005. Lethality ranging up to 20% with death caused most often by intracranial hemorrhage.
Caterpillars do not have good vision. They have a series of six tiny eyelets or 'stemmata' on each side of the lower portion of their head. These can probably form well focused, but poorly resolved images. They move their heads from side to side probably as a means of judging distance of objects, particularly plants. They rely on their short antennae to help them locate food. Some caterpillars are able to detect vibrations, usually at a specific frequency. Caterpillars of the common hook-tip moth, Drepana arcuata (Drepanoidea) produce sounds to defend their silk nests from members of their own species, by scraping against the leaf in a ritualized acoustic duel. They detect the vibrations conducted by the plant and not airborne sounds. Similarly, cherry leaf rollers Caloptilia serotinella defend their rolls. Tent caterpillars can also detect vibrations at the frequency of wing beats of one of their natural enemies.
Many animals feed on caterpillars as they are rich in protein; adversely, caterpillars have evolved various means of defenses. The appearance of a caterpillar can often repel a predator, the markings and certain body parts can make it seem poisonous, bigger in size thus threatening, or non-edible. Some types of caterpillars are indeed poisonous, and are capable of shooting acid. Some caterpillars have long "whip-like" organs attached to the ends of their body. The caterpillar wiggles these organs to frighten away flies. Caterpillars have evolved defences against physical conditions such as cold, hot or dry environmental conditions. Some Arctic species like Gynaephora groenlandica have special basking and aggregation behaviours apart from physiological adaptations to remain in a dormant state.
Caterpillar hairs have also been known to cause kerato -conjunctivitis. The sharp barbs on the end of caterpillar hairs can get lodged in soft tissues and mucus membranes such as the eyes. Once they enter such tissues, they can be difficult to extract, often exacerbating the problem as they migrate across the membrane. This becomes a particular problem in an indoor setting. The hairs easily enter buildings through ventilation systems and accumulate in indoor environments because of their small size, which makes it difficult for them to be vented out. This accumulation increases the risk of human contact in indoor environments.
Bird
Kingfisher
The Common Kingfisher, Alcedo atthis, also known as Eurasian Kingfisher orRiver Kingfisher, is a small kingfisher with seven subspecies recognized within its wide distribution across Eurasia and North Africa. It is resident in much of its range, but migrates from areas where rivers freeze in winter. This sparrow-sized bird has the typical short-tailed, large-headed kingfisher profile; it has blue upperparts, orange underparts and a long bill. It feeds mainly on fish, caught by diving, and has special visual adaptions to enable it to see prey under water. The glossy white eggs are laid in a nest at the end of a burrow in a riverbank.
A challenge for any diving bird is the change in refraction between air and water. The eyes of many birds have two foveae (the fovea is the area of the retina the greatest density of light receptors), and a kingfisher is able to switch from the main central fovea to the auxiliary fovea when it enters water; a retinal streak of high receptor density which connects the two foveae allows the image to swing temporally as the bird drops onto the prey.The egg-shaped lens of the eye points towards the auxiliary fovea, enabling the bird to maintain visual acuity underwater. Because of the positions of the foveae, the kingfisher has monocular vision in air, and binocular vision in water. The underwater vision is not as a sharp as in air, but the ability to judge the distance of moving prey is more important than the sharpness of the image.
Each cone cell of a bird’s retina contains a oil droplet which may contain carotenoid pigments. These droplets enhance colour vision and reduce glare. Aquatic kingfishers have high numbers of red pigments in their oil droplets; the reason red droplets predominate is not understood, but the droplets may help with the glare or the dispersion of light from particulate matter in the water. The Common Kingfisher hunts from a perch 1–2 m (3–6 ft) above the water, on a branch, post or riverbank, bill pointing down as it searches for prey. It bobs its head when food is detected to gauge the distance, and plunges steeply down to seize its prey usually no deeper than 25 cm (19 in) below the surface. The wings are opened under water and the open eyes are protected by the transparent third eyelid. The bird rises beak-first from the surface and flies back to its perch. At the perch the fish is adjusted until it is held near its tail and beaten against the perch several times. Once dead, the fish is positioned lengthways and swallowed head-first. A few times each day, a small greyish pellet of fish bones and other indigestible remains is regurgitated.
The food is mainly fish up to 12.5 cm (4.9 in) long, but the average size is 2.3 cm (0.91 in). Minnows, sticklebacks, small roach and trout are typical prey. About 60% of food items are fish, but this kingfisher also catches aquatic insects such as dragonfly larvae and water beetles, and, in winter, crustaceans including freshwater shrimps.
Common Myna
The Common Myna or Indian Myna (Acridotheres tristis) also sometimes spelled Mynah, is a member of family Sturnidae, (starlings and mynas) native to Asia. An omnivorous open woodland bird with a strong territorial instinct, the Myna has adapted extremely well to urban environments. The myna has been introduced in many other parts of the world and its distribution range is on the increase. It is a serious threat to the ecosystems of Australia. The Common Myna is an important motif in Indian culture and appears both in Sanskrit and Prakrit literature. The Common Myna is readily identified by the brown body, black hooded head and the bare yellow patch behind the eye. The bill and legs are bright yellow. There is a white patch on the outer primaries and the wing lining on the underside is white. The sexes are similar and birds are usually seen in pairs.
The Common Myna obeys Gloger's rule in that the birds from northwest India tend to be paler than their darker counterparts in South India. Common Mynas are believed to pair for life. They breed through much of the year depending on the location, building their nest in a hole in a tree or wall. They breed from sea-level to 3000 m in the Himalayas.
The normal clutch size is 4–6 eggs. The average size of the egg is 30.8 x 21.99 mm. The incuation period is 17 to 18 days and fledging period is 22 to 24 days. The Asian Koel is sometimes brood parasitic on this species. Nesting material used by mynas include twigs, roots, tow and rubbish. Mynas have been known to use tissue paper, tin foil and sloughed off snake-skin.During the breeding season, the daytime activity-time budget of Common Myna in Pune in April to June 1978 has been recorded to comprise the following: nesting activity (42%), scanning the environment (28%), locomotion (12%), feeding (4%), vocalisation (7%) and preening-related activities, interactions and other activities (7%).
The Common Myna uses the nests of woodpeckers, parakeets, etc. and easily takes to nest boxes; it has been recorded evicting the chicks of previously nesting pairs by holding them in the beak and later sometimes not even using the emptied nest boxes. This aggressive behavior is considered to contribute to its success as an invasive species. Like most starlings, the Common Myna is omnivorous. It feeds on insects, arachnids, crustaceans, reptiles, small mammals, seeds, grain and fruits and discarded waste from human habitation. It forages on the ground among grass for insects, and especially for grasshoppers, from which it gets the generic name Acridotheres, "grasshopper hunter". It however feeds on a wide range of insects, mostly picked from the ground. It is a cross-pollinator of flowers such as Salmalia and Erythrina . It walks on the ground with occasional hops and is an opportunistic feeder on the insects disturbed by grazing cattle as well as fired grass fields.
Dragonfly
A dragonfly is an insect belonging to the order Odonata, the suborder Epiprocta or, in the strict sense, the infraorder Anisoptera. It is characterized by large multifaceted eyes, two pairs of strong transparent wings, and an elongated body. Dragonflies are similar to damselflies, but the adults can be differentiated by the fact that the wings of most dragonflies are held away from, and perpendicular to, the body when at rest. Dragonflies possess six legs (like any other insect), but most of them cannot walk well. Dragonflies are some of the fastest insects in the world. Tillyard claimed to have recorded the Southern Giant Darner flying at nearly 60 miles per hour (97 km/h) in a rough field measurement. However, the greatest reliable flight speed records are for other types of insects. In general, large dragonflies like the hawkers have a maximum speed of 10–15 metres per second (22–34 mph) with average cruising speed of about 4.5 metres per second (10 mph).
Damselflies (suborder Zygoptera), typically being smaller than dragonflies, are sometimes confused with newly moulted dragonflies. However, once a dragonfly moults, it is already fully grown. There are other distinctions that set them apart: most damselflies hold their wings at rest together above the torso or held slightly open above (such as in the family Lestidae), whereas most dragonflies at rest hold their wings perpendicular to their body, horizontally or occasionally slightly down and forward.
Also, the back wing of the dragonfly broadens near the base, caudal to the connecting point at the body, while the back wing of the damselfly is similar to the front wing. The eyes on a damselfly are apart; in most dragonflies the eyes touch. Notable exceptions are the Petaluridae (Petaltails) and the Gomphidae (Clubtails).
WATER MONITOR
The Water monitor, (Varanus salvator) is a large species of monitor lizard capable of growing to 3.21 metres (10.5 ft) in length, with the average size of most adults at 1.5 metres (4 ft 11 in) long.[1] Maximum weight of Varanus salvator can be over 25 kilograms (55 lb), but most are half that size. Their body is muscular with a long, powerful, laterally compressed tail. Water monitors are one of the most common monitor lizards found throughout Asia, and range from Sri Lanka, India, Indochina, the Malay Peninsula and various islands of Indonesia, living in areas close to water.
Water monitors can be defensive, using their tail, claws, and jaws when fighting. They are excellent swimmers, using the raised fin located on their tails to steer through water. Water Monitors are carnivores, and have a wide range of foods. They are known to eat fish, frogs, rodents, birds, crabs, and snakes. They have also been known to eat turtles, as well as young crocodiles and crocodile eggs
Like the Komodo Dragon, they will often eat carrion.
Hong Kong, it is a protected species under Wild Animals Protection Ordinance Cap 170. In Malaysia, this species is one of the most common wild animals around with numbers comparable to that of the population of macaques there. Although many fall prey to humans via road kill and animal cruelty, it still thrives in most states of Malaysia especially in the shrubs of the east-coast states such as Pahang and Terengganu.
. Malay "kampung" boys and young working class malay men often catch and kill water monitors for their own amusement although the widespread population of the species causes the lack of conservation attention. In the east-coast states of Malaysia, this species is very common in roadkill. In Thailand, all monitor lizards are protected species.
Spider
Spiders (order Araneae) are air-breathing arthropods that have eight legs, and cheliceraewith fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms.Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every habitatwith the exception of air and sea colonization. As of 2008, approximately 40,000 spiderspecies, and 109 families have been recorded by taxonomists; however, there has been confusion within the scientific community as to how all these families should be classified, as evidenced by the over 20 different classifications that have been proposed since 1900.
Anatomically, spiders differ from other arthropods in that the usual body segments are fused into two tagmata, the cephalothorax and abdomen, and joined by a small, cylindrical pedicel. Unlike insects, spiders do not have antennae. In all except the most primitive group, theMesothelae, spiders have the most centralized nervous systems of all arthropods, as all theirganglia are fused into one mass in the cephalothorax. Unlike most arthropods, spiders have no extensor muscles in their limbs and instead extend them by hydraulic pressure.
Their abdomens bear appendages that have been modified into spinnerets that extrude silkfrom up to six types of silk glands within their abdomen. Spider webs vary widely in size, shape and the amount of sticky thread used. It now appears that the spiral orb web may be one of the earliest forms, and spiders that produce tangled cobwebs are more abundant and diverse than orb-web spiders. Spider-like arachnids with silk-producing spigots appear in theDevonian period about 386 million years ago, but these animals apparently lacked spinnerets. True spiders have been found in Carboniferous rocks from 318 to 299 million years ago, and are very similar to the most primitive surviving order, the Mesothelae. The main groups of modern spiders, Mygalomorphae and Araneomorphae, first appear in the Triassic period, before 200 million years ago
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A vegetarian species was described in 2008,[4] but all other known species are predators, mostly preying on insects and on other spiders, although a few large species also take birds and lizards. Spiders use a wide range of strategies to capture prey: trapping it in sticky webs,lassoing it with sticky bolas, mimicking the prey to avoid detection, or running it down. Most detect prey mainly by sensing vibrations, but the active hunters have acute vision, and hunters of the genus Portia show signs of intelligence in their choice of tactics and ability to develop new ones. Spiders' guts are too narrow to take solids, and they liquidize their food by flooding it with digestive enzymes and grinding it with the bases of their pedipalps, as they do not have true jaws.
Male spiders identify themselves by a variety of complex courtship rituals to avoid being eaten by the females. Males of most species survive a few matings, limited mainly by their short life spans. Females weave silk egg-cases, each of which may contain hundreds of eggs. Females of many species care for their young, for example by carrying them around or by sharing food with them. A minority of species are social, building communal webs that may house anywhere from a few to 50,000 individuals. Social behavior ranges from precarious toleration, as in the aggressive widow spiders, to co-operative hunting and food-sharing. Although most spiders live for at most two years, tarantulas and other mygalomorph spiders can live up to 25 years in captivity.
Spiders reproduce sexually and fertilization is internal but indirect, in other words the sperm is not inserted into the female's body by the male's genitals but by an intermediate stage. Unlike many land-living arthropods, male spiders do not produce ready-made spermatophores (packages of sperm) but spin small sperm webs on to which they ejaculate and then transfer the sperm to syringe-like structures on the tips of their pedipalps. When a male detects signs of a female nearby he checks whether she is of the same species and whether she is ready to mate; for example in species that produce webs or "safety ropes", the male can identify the species and sex of these objects by "smell".
Females lay up to 3,000 eggs in one or more silk egg sacs, which maintain a fairly constanthumidity level. In some species the females die afterwards, but females of other species protect the sacs by attaching them to their webs, hiding them in nests, carrying them in the chelicerae or attaching them to the spinnerets and dragging them along.
Baby spiders pass all their larval stages inside the egg and hatch as spiderlings, very small and sexually immature but similar in shape to adults. Some spiders care for their young, for example a wolf spider's brood cling to rough bristles on the mother's back, and females of some species respond to the "begging" behaviour of their young by giving them their prey, provided it is no longer struggling, or evenregurgitate food.
Like other arthropods, spiders have to molt to grow as their cuticle ("skin") cannot stretch. In some species males mate with newly molted females, which are too weak to be dangerous to the males. Most spiders live for only one to two years, although some tarantulas can live in captivity for over 20 years.
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