Living World – 6 Rainforest Interdependence & Adaptations
●Watch the video below for a recap from this unit and a reminder what will be covered this week from Mr Price at BMA who is leading these lessons
Interdependence in the Rainforest
Interdependence is the idea that the different aspects of life in the rainforest, both living (biotic) and non-living (abiotic), all interact and depend on one another. A change to one of these parts will have a knock-on effect to other parts of the system. We will explore some of the links in the questions below. However as an example of how interlinked the system is, let’s consider the soil. The quality of the soil will directly impact how well trees will grow, or the way in which they will grow. Animals are then reliant on these trees in order to find food or to live in. When leaves from the trees fall to the ground, the decompose and return nutrients back to the soil. The climate will also impact the growth of the vegetation, and any rainfall that makes it to the forest floor will have a direct impact on the soil. This is interdependence.
Study the diagram below and answer the questions:
Look at the scenarios listed below, and think about what the knock-on would be to the other aspects of the rainforest ecosystem. Click to reveal the answers.
1) If the amount of rainfall decreased… (change to climate)
2) If a large area of trees is removed… (change to vegetation/plants)
3) If a new species of animal is introduced to the area… (change to animals)
- This could impact on the growth of vegetation, leading to less growth.
- The impact on the animals would be huge. If large areas are deforested then that will reduce the potential habitats available for the animals to live in, and also reduce their source of food. It would also impact the soil as there would be fewer leaves falling to the ground and returning nutrients to the soil.
- This new species may live off a different type of tree, and therefore change the amount of vegetation.
Animal Adaptations in the Rainforest
Adaptation is where plants and animals have adjusted and changed in order to be able to survive in the conditions of their habitats. For animals, this may be adaptations to help with food, shelter or escaping prey. Watch the video below from 3 mins 40 seconds to discover some of the animal species found in the Amazon Rainforest. How many adaptations can you spot?
What do you think is the purpose of each of these animal adaptations is? In what ways will it help an animal survive in the rainforest? Write your answers and then click to reveal. Bonus: can you name an animal that has this adaptation?
2. Long, hard bill
4. Strong limbs
- Being camoflauged helps animals to avoid predators. (eg sloth/leaf tailed geckos)
- This helps birds to reach and cut fruit from branches. (eg toucan)
- By operating at night, the nocturnal animals avoid the heat of the day. (eg sloths)
- This would allow the animal to climb and swing through the trees in the canopy. (eg howler monkey)
Plants have also adapted to the conditions in the rainforest. There is a lot of competition for sunlight, and a high level of rainfall to contend with. Here are a few images of adaptations to plants in the rainforest. Take a look and then attempt the activity below.
Sketch a rainforest tree, or group of trees and add the following labels:
a. buttress roots
b. drip-tip, waxy leaves
c. smooth bark
For each of the labels, try to match the explanation. Answers follow by clicking below:
1. This means that the tree can reach sunlight up in the canopy layer of the rainforest.
2. These plants live on and grow from other trees in the forest and get their nutrients not from the soil, but from air and water.
3. These help the tree by providing a strong supporting base, and searching for nutrients over the forest floor, rather than deep into the poor soil.
4. This allows the leaf to funnel any excess water away and to the ground, and means the leaf won’t rot.
5. This adaptation helps the tree in two ways. Firstly it means it is easier for rainwater to flow down to the roots, and secondly it makes it more difficult for other plants to grow on the tree.
a – 3
b – 4
c – 5
d – 2
e – 1
Although not great quality, this clip from David Attenborough and the BBC takes a closer look at how trees grow and find sunlight in the dense rainforest.
Issues related to biodiversity
The final point in the GCSE spec for this section simply says ‘Issues related to biodiversity’. We have already covered some of this when talking about interdependence. Due to the interconnected nature of ecology and ecosystems, anything that causes change within the ecosystem is therefore a threat to biodiversity.
The two biggest threats to the biodiversity in the rainforest are a changing climate, and human activity. In general, it is fair to say that most human activity has reduced biodiversity.
Task: For each scenario below, explain firstly how it will impact biodiversity (the number of different species in the rainforest) and secondly, how it will have a further impact on the other aspects of the ecosystem (climate | soil | vegetation | animals) due to it being interdependent.
– A large area of hardwood trees has been cut down by a logging company to make paper.
– There has been a lack of rainfall for the first 6 months of the year in the Amazon region of Brazil.
– Poachers have been in and removed a significant number of wild birds for the illegal pet trade.
Extension- Below are a number of exam style questions based on the content covered today. Either answer the questions, or plan what content you would include in your response.
1. Explain how the soil and plants in the tropical rainforest are dependent on one another. (2)
2. Describe and explain two plant adaptations found in the rainforest. (4)
3. Describe and explain two animal adaptations found in the rainforest. (4)
4. Explain how human development of a tropical rainforest might reduce biodiveristy. (4)
1)Download the keywords and learn the definitions
2) Complete the revision and test from BBC Bitesize on rainforests using the button below (this was set last week in the blog post too)
Some activities and images used have been resourced from GCSE Geography AQA -Simon Ross, Nicholas Rowles, David Holmes, Bob Digby. Published by Oxford.