Message de neilime posté le 2004-11-17 18:52:41 (S | E | F | I)
Bonjour,
j'aimerai un peu d'aide pour connaitre votre avis sur un petit exposé en anglais sur les serpents. Le sujet n'est vraiment pas poussé mais je pense que ça suffit, j'aimerai me concentrer plus sur l'anglais.
Donc si qqn aurait la gentilesse de me corriger, ce serait top !!!


BETTER RECOGNIZE THE SNAKES OF YOUR REGION.

Snakes can be as attractive as fearful. Even if they are fascinating, we are positive that some of them are really dangerous. Consequences are dramatic for snakes itself because by fright on the one hand, or by ignorance on the other hand, they are often killed without any discrimination.
That’s why, thanks to this brief presentation, we will try to make you have a better knowledge of snakes and, why not, to make you appreciate them!

I/ Snakes’ biology: main characteristics

- In contrast with birds and mammals, which generate their own body heat, snakes are “ectotherms”, that’s to say the temperature of their body depends on an external source, like the sun.

- The snake’s skin is covered of rigid scales.
These scales play an important part in the protection and the camouflage of the animal.
However, in order to grow, snakes must change their skin and their scales periodically. It is the phenomenon of moulting.

- The snake’s anatomy, despite their shape and length, is nearly the same than others vertebrates.
Indeed, they dispose of the same organs, but their arrangement is not the same because of a too narrow body. It is not large enough.
By the way, the disappearance of the left lung can be noticed.

- The snake’s sensory system has two major particularities.
In a first place, snakes don’t have external ear; therefore they are deaf.
In a second place, snakes have a particular olfactory organ, which allow them to smell with their tongue.

- To conclude with this first part, it is important to remember that a major part of snakes are oviparous, that’s to say they lay eggs.

II/ The clues to distinguish a venomous snakes : Grass-snake / Viper.

1. Furtive observation.

The grass snake moves very quickly and noisily, whereas viper is quiet and discreet.
A difference can also be observed on a part with their tails: grass snake has a lengthier tail than the viper, which is particularly short.

2. Complete observation of body.

The grass snake maximum height is about 2m while the highest viper are about 85 cm long. Moreover, the heads of this two species are significantly different. In fact, grass snake has a rounded-shaped head, very different of the triangular head of vipers.



3. Detailed observation.

One more time, it is the head of the two kinds of snakes that will allow us to do a pertinent discrimination.
Grass snake possesses 9 large scales on their head; at the opposite viper has a lot of very little scales.
In addition, there is one line of scales between the grass snake’s upper lip and their eyes. In return, viper has two or three of these lines.

Nevertheless, the major difference can be observed on a part with pupils.
Indeed, grass snake has circular pupils, whereas viper has vertical ones.

Merci d'vance




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Edité par bridg le 17-11-2004 19:13
Comme convenu je t'en ai retiré la moitié tu posteras l'autre moitié ensuite dont je t'envoie un copier/coller pour que tu n'aies pas à le réécrire