 Dear learners, now we will know something about snakes, how they live the mood of life and different types of adaptations for their life history strategies we know about in this topic. So snakes as you know, snakes are the most evolved reptiles of reptiles and they are have a very very special characteristic. So first of them and it's common to all the reptiles is that snakes are also ectotherm. Ectotherm means they cannot regulate their body temperature. So to maintain their body temperature they depends on the external source that is the sun. So that's why we see snakes or other reptiles come out in the morning and they bask under the sun. So that from there they regulate the body temperature and they can also digest their food. So that's why they are ectotherm and we mammals we are endothermic animals. So their body is covered by scales like most of the reptiles also their body is covered by scales. This is one of the character and the most important character of the snake which make a snake is that snakes don't have any limbs. They don't have any hind limb and either they have a forelimb. So they are completely devoid of limbs. And another characteristic that makes snake unique is that snake don't have a maxillary joint. So their both upper and lower jaw are not joined at the posterior part. And that's why snake can expand its mouth more than we can imagine. And that's why a small snake can ingest a very large prey. Just imagine that how python can eat a large deer. So that is the only reason why because they have a don't have a maxillary joint. So they can they can take a big food and they take the food to hold. They never chew it. And another characteristic of the snake is that they don't have any eyelids. So all the lizards they have eyelid but snakes don't have eyelid. And another character is that snake don't have any ear opening. So the ear opening what we have or other animals have snake don't have that. So and snakes are the most recent of all the reptiles. So by photography also we can say so this is a lizard and this is a snake. And here we can see the ear opening in lizard is present here but snakes don't have any ear opening. And then coming to the eyelid we can see here in lizard they have eyelid. So they can close the eye but in case of snakes they don't have any eyelid. So it is eye is always open. So shape and size snakes as you know one of the most remarkable animals and their diversity life form is is of tremendous tremendous value to nature also. And because they have a different type of shape and size. So we we get a lot of snakes which are we known as blind snakes. They grow live under soil and since they live under soil they don't need the eye. So their eye is almost vestigial. So they are also known as blind snake which only grow 10 to 30 centimeter long. And then we we see a lot of snakes around us which grow one to maybe six feet long. So most of the our native snakes grow fall into this category but snake also can grow up to 35 feet. So this is one of the picture it's like anaconda which is such big snake can eat a large crocodile also but the longest recorded snake is a reticulated python which is recorded as 35 feet long. Color and variety snakes color and variety is unmatched the only animal can match with the color and variety is the butterflies. So we have astonishing diversity in color and form. So this is one of the wine snake non-venomal snake and it's known as wine snake because his body is very thin and it completely matches with the vines of the forest and it's tail like this. So this is one of the green snake of the forest. Then we have very common species in asamese it is known as bamuni half very common and we have this buff colored strip running all along the body. So this is a very small hardly one feet to 1.5 feet long and it's very common snake in an around our houses but this is one of the forest species this is known as cat snake. Why cat snake because their eyes you can see it's like more like cat and these cat snakes are feed on lizards and birds. So these they are nocturnal snake they come out in the nighttime. So this is you can see plain brick colored and then another beautiful snake is the dendrolophus or the bronzeback tree snake. So these bronzeback tree snake they stay on the forest vegetation and they are very fast moving and you can also see they have a very large eye. So these are all non-venomous and having the diversity in coloration. You can see this coloration in the middle of their scales. So whenever somebody wants to kill them or catch them they expand their body and they show this coloration. So this is one of the warning coloration for this snake. Then we have another green snake. So this is another cat snake it comes out in the nighttime and they live on the high on trees and they feed on birds. So this is a green cat snake and then we have another species called raptophis the redneck killback. So this redneck shows that they have a redneck on so that's why they are known as redneck killback and why they are killback because their scales are very highly killed that is their scales are not rough they are very they have their scales are rough and not smooth. So this one of the characteristic and then another this is called the eastern cat snake with a beautiful pattern on the y-shaped pattern on the body and the arrow head shape mark which is very common around Guwahati city and then beautiful lycodon or wolf snake. All the scales of the body is like having two yellow spots. So and then another mountain snake which is found in Arunachal Pradesh it's a blueish body with a yellow particular bands dorsolaterally. So this one of the this is a aquatic snake and we from this we can imagine the diversity in color and form in snakes. Also snake are the animal which inhabit almost all parts of the earth and without any hands and limbs they can they can be present anywhere. So this blind snake as I already told you they don't have a eye so they live under soil and they move under soil also they feed on ant and termite larvae. So because they live under soil they don't need the function of eye. So their eye is rudimentary and then there are some a lot of snakes we see on the ground. So these ground wailing snakes are very fast moving. You can see the body when they move there are some first portion of the body comes above the soil and so these are terrestrial snakes and diurnal species we we see many of these animals. Then there are other snakes which live on the trees also. So without hands and limbs they can climb straight trees. So this is very unique how they do this. So the three snakes they developed a very rough scales along their belly. So what happened with this rough scales they can easily climb the vertical surface and their body weight is very low so which aid in their climbing. And then there are so many snakes which live in the water also although there are sea snakes but we don't have sea snakes in northeast India but we have some other aquatic snakes. The most famous is the Dhorahap we call or Xenocropus or common water snake. So these water snakes one adaptation they developed is that their nostril opening is is located slightly upward. So since it is located slightly upward it helps in movement along the along the water. So water is not easily go into the nostril. So by the looking at the eye we can say which snake is can move at what time. So this is a round pupil. So round pupil signifies that this snake is a day moving snake day active snake and then we have vertical pupil. So all the vertical pupil snake we largely they are night active snakes and then there is very special pupil arrangement in case of blind snake what we saw the first they have the horizontal pupil. So horizontal pupil means they have a binocular vision while catching lizards. So as we we all probably have seen snakes and we also saw that snakes while they move or they every time they take out their tongue why they do this. This is just because tongue is the most important sense organ for the snakes. As you know snakes do not have a R opening. So it is the airborne sound which produces it is very it is it is not very much accepted by the snake. So they do not depend much on the airborne sound rather they depend on their tongue. So whenever snake comes out they take their tongue out and take the chemicals of the surrounding environment and again take it inside the tongue when they take it inside snake have a very important organ called Jacobson organ on the top of their mouth floor. So when this chemicals were taken to the Jacobson organ then brain can analyze what is what is there in their surrounding by which they can sense and also snakes most of the vibration of the surrounding environment they take it through their body. So that is why they are very sensitive to the vibration. So as you know snakes all the animals have different types of defense mechanism and defense is the most primary for somebody's life. So in animal kingdom we have two different type of defense mechanism one is passive defense mechanism and one is active defense mechanism and snakes these two defense mechanism are very very pronounced. So in reptiles we see like this you know you can you see this this is a gecko or flying gecko and they completely matches with the with the free bark where they say. So this is one of the passive defense like you know our army our cops so they have a combat dress while they are fighting in the forest. So why combat dress because that combat dress give them the passive defense that is nobody can see them in the forest. So just like that animals also develop adaptation by which other animals cannot see them. So this is you can see this is a surface where this snakes stay and this snakes coloration exactly matches with the surrounding. So this is one of those adaptation then can you see some what is there something very peculiar but from the distance it will be very difficult to identify but here there is one lizard and this lizard is exactly matching with the rocks surrounding. So nobody can identify what is there and it's any the predator like birds or other snakes cannot also identify so that's why it will be saved. And here in barrail wildlife century also we have seen this is a stream and this is a road also and we we we go this way and this is one snake which coiled among the leaf and it is although this all these leaves are touching everybody's head but nobody can see them. So this is one of the defense mechanism they exactly match with the surrounding and this one of those acrochord snake one of the salt water snake as you see it's near the sea shore it completely gone under the mud and staying there just opening the nostril so that it can take oxygen. And then this another cat snake after feeding all the birds it's staying inside the bird nest so when the there will be digestion is over it will go out. So and then this is another general of this it's it's called in asame it is not carcola so this this snake is mimics like dry branch so whenever there is a dry branch this snake will go in onto that and it will extend its body like another dry branch so from the distance somebody will not recognize it is a snake but it is a dead branch. But these are the passive defense but there are some active defense also so whenever passive defense is over whenever somebody will catch them or try to kill them then they will show some active defense. So this is one of the kukri snake or oligodon which is found in Nagaland so this snake whenever somebody wants to catch it so it immediately hide its head and raise its tail and display the tail in a circular fashion. So this is one of the remarkable display because he knows that his head is the most important organ for him so he tries to save the head and in that way he raised the tail so predatory concentration from the head will be diverted to the tail and in this way he will be saved. Then another snake so I ask people what is this snake so most of the people they said this is a cobra so why cobra because it's taking a hood but actually this is one of the most common snake called water snake or Dora half so Dora half or water snake some of them came to know that there is a very dangerous snake called cobra and people are afraid of cobra so just knowing that he is now mimicking like a cobra so venomous species people will be afraid of him and he will be saved although he knows that I don't have any venom. So then another remarkable display whenever somebody tries to kill the snake so snake take different dangerous position with you can see the air opening here so with this opening and closing of that bokeh seck they produce the hissing sound so by this way they try to save themselves by active defense and there is the most remarkable display you know the most famous snake in India is the cobra with whenever somebody threaten a cobra it raise the hood show that don't come near me or I will bite you so these are the different mechanism by which they try to avoid confrontation and this is one of the most remarkable snake although we don't have enough this so far this is a spitting cobra so whenever somebody try comes near it it raise the hood and if then also that animal is coming to kill it or eat it then it spray the venom dart the venom to the eye of the predator and in that way he can save himself so this defense mechanism the main motto of this defense is that all the animals try to avoid confrontation because all the venoms or any other things they are the very very precious commodity for any animal or also the snake so snake always try to save or conserve this venom and which will be which will be like you know destroyed if he comes he comes in concentration with the confrontation with the human being so this is another green cat snake as we saw the picture so it has a black mouth inside so whenever we try to catch it or we go near it it open the mouth and show the black portion of the mouth so in this way he tries to save himself so this indifferent mechanism so with this end we came to an end of this diversity in snake and also their defense mechanism