Wednesday, March 9, 2011

Common name and Binomial name

Common name: Golden Web Spider, Giant Wood Spider
Some refer to it as Banana Spider, often confused with the South African Banana Spider

Binomial name: Nephila Maculata

Appearance

The Nephila Maculata is the largest of the Golden orb spiders and the Family Araneidae (Orb web spinning spiders)


Female: The females have yellow spots on their black legs with spots of yellow, black, red or sometimes white as you can see on the photo to the right. The female is much bigger than the male, some males are 1000 times smaller than the female.


Male: The males are smaller than the female with yellow spots on their black legs, but they do not have any spots on their bodies. They have red fangs as shown in the photo on the right.


The Golden web spider lives in the Mangroves and tropical rain forests of Singapore, Indonesia, Cambodia, Japan, Africa, India, China, Australia and the South Pacific Island.

Trophic Level
The Golden web Spider is usually on the 3rd trophic level as it eats insects (2nd trophic level) that feeds on plants (1st trophic level).

Adaptation

Webs: Strong and big
The Golden web spider is well known for its strong webs. It is strong and big enough to catch preys much bigger than the spider itself such as birds,
though it does not eat birds,
grasshoppers and other insects.
The web can be 6 meters high and 2 meters wide. Unlike other spiders' webs, the Golden web spider's webs can last for many years which means it does not have to constantly mend its web after a prey has been caught.

This helps the Golden web spider to survive in the Mangrove of Singapore as the Spider has a higher chance of catching preys due to the Golden web spider web's size and golden color, which attracts them and their web's strength will guarantee a meal as the prey will not be able to escape from the web.

Attractive?
Many people think that the yellow spotted legs are there to attract preys at night so that the black parts of the spider is camouflaged while the yellow spots 'glows'.

This helps the Golden web spider to survive as the Golden web spider will have a lot of preys to eat as it attracts them to the spider, so the Spider will not be short on food.

Venomous
Like the others in the Golden orb spider (Nephila) family, the Nephila Maculata is venomous, but it is not lethal to kill a human. If a human does get bitten by one they say it is barely a scratch.

This helps the Golden web spider to survive as the venoms will be able to kill the preys instantly, which means there will be no hassles with trying to keep the prey still and not damage the web.

Sudden Increase

If there is a sudden increase in the numbers of Golden web spiders, the Golden web spiders will eat up nearly all the Grasshoppers, which means it will have to rely on other sources of foods such as other insects, but because of the large number, there will be competitions amongst themselves. Looking at the food web, the Common Redshank also eats Grasshoppers, so it will have to rely on the Tree climbing crabs as source of food in this case. However, the Common Redshank does not have to worry as there are plenty of Golden web spiders to eat. If there are less or no Grasshoppers eating the Mangrove plants, the plants will thrive in numbers and the Tree climbing crab will have more plants to feed on, so it will eat more plants than anything else.

Sudden Decrease
If there is a sudden decrease in the numbers of Golden web spiders, the Grasshopper will thrive better than before as it has less predators eating it. The Common Redshank will have less Golden web spiders to feed on, but it has the Tree climbing crabs and the Grasshoppers to feed on. This will result in an unbalanced population of Grasshoppers because there is only one predator trying to control the population of the Grasshoppers.

Human Impact on the Mangrove ecosystem
Humans are destroying homes for the inhabitants in the Mangrove ecosystem.
For:
Humans are cutting down trees, which are homes to many species of the Mangrove ecosystem. In fact most of them rely on trees as shelters. If humans are cutting down trees, the inhabitants will have to move to a different place, possibly out of the Mangrove. There are not many Mangroves left in this world, Mangroves are important for our foods such as fish, prawn, fruits (eg: Durian).

Against:
We are not cutting down every single trees, just in pockets. We humans also rely on trees for resources such as fire woods, paper, rubber. It is human nature to cut down tree to use it for our needs just like the animals.

Humans are turning Mangroves into junkyards.
For:
Humans are littering in Mangroves as you can see in the picture. The Mangrove does not deserve to be littered, it is a home to many living things and littering their home is against animal rights.

Against:
Cleaning processes are occurring at the Mangrove. Installed fences in waters (eg: Sungei Buloh) to prevent trashes floating away to the animals, which could possibly mistake it as foods. It also helps the cleaning process as there is no need to hassle collecting all the trashes that had drifted away.

AOI
The AOI for this topic is Environment because we have explored one of many organisms in the Magrove, Sungei Buloh about its appearance, adaptation, and looked at its food chain/web. We have also explored the chain reaction in the food web if that particular organism’s number increased and decreased and the human impact on the Mangrove.

Word count: 923 words (including the subtopics)