Predator/Prey Activity

   In this lab activity, our objective was to investigate how populations are affected by predator-prey relationships over several generations. We did not have enough time so we only did one environmental situation. We chose a tropical environment that had four variations of rabbits (green, light green, yellow and white) and 2 variations of wolves (big and small). By analyzing our data, we could make conclusions on predator-prey relationships affect on our population and make assumptions about other populations in different environments. Here the rabbit is the primary consumer and the wolf is the secondary consumer. The game starts with the 4 variations of rabbit on the land. A wolf is picked out randomly from a bag and thrown onto the land. If the wolf catches a rabbit, then the rabbit dies, but if the wolf does not catch three rabbits in one throw, then it also dies. 

Wolves	Rabbits
1 L	1G 1LG 1Y 1W
1 S	2G 2LG
1 L	4G 2LG
1 L	8G 6Y
1 L	16G 21Y
2 L	20G 24Y
1 L	14G 16Y
1L 1S	22G 24Y
4L 1S	40G 26Y
4L 8S	48G 32Y
1S	1G 1LG 1Y 1W
2S	2G

A generation lives off of the amount of food and energy in the environment. As you can see in this chart, the rabbits greatly increased from the wolves because their is not enough energy for the wolf to survive. The wolf then dies due to starvation and the lack of energy to sustain it. The Dark Green rabbit was the better adapted and could camouflage in the tropical forest better than the other rabbits. The white rabbit was least adapted and was the first to be extinct. I observed that the wolves increased when the rabbits reached their peak and their was enough food for the wolves. At the end, all the wolves and rabbits died of starvation, and a new generation was formed. 

Natural DisAsTeR

 Bark Beetle Invasion in the Amazon Tropical Rainforest 

A Bark Beetle invasion has caused massive destruction in the Amazon Rainforest. These insects have co-evolved over thousands of years with their host trees and an integral part of forest ecosystems. They usually feed on dead bark, but when their is not enough they move to healthy trees. These Bark Beetles have taken up residence, killed trees and disturbed ecosystems. 

Trees produce a volatile chemical that keeps the beetles away, however when overcrowding occurs, the trees lack energy to produce its normal mix of terpenes and releases other chemicals that the bugs can sense. The beetles sense the change in chemicals and know it is easy to attack. Female beetles bore into the bark of the tree and release a pheromone that attracts male beetles into the phloem layer of the tree. Thousands of beetles are then born in the tree. These beetles destroyed the vascular tissues that conduct water and nutrients in the tree.

Bark beetles also cause climate change that can be very detrimental to the lack of seasonal change in the rainforest. They cause drought and forest fires. This also hurts the wildlife of the forest. 

Animals who use trees as shelter like monkeys and sloths would be in great danger as more trees would die and collapse. Animals that use the trees for food such as birds and insects. 

Fungus is better adapted to the bark beetle invasion through evolution. Bark beetles and fungus have formed a symbiotic relationship. Fungus helps overcome the tree so that the beetles can feed on the tree as they carry fungal spores in their special structures. Termites and ants also emit chemicals that attracts the beetles to the trees. 

The tropical rainforest has less and less trees and will take a while to gain the trees back. Many animals are left without food and a home. The trees will eventually grow back strong with time. Once the trees are back, the beetles will create a variety of levels of trees that supports the canopy and animals that live within them.