9. (a) (i) What is meant by the term `fauna`? (ii) In ecological studies what is a key? (b) Name five plants in the ecosystem that you have studied - Leaving Cert Biology - Question 9 - 2006

In ecological studies, a key is a systematic tool that aids in identifying organisms. It presents choices based on observable characteristics that lead the user through a series of questions or statements, ultimately assisting in the identification of species.

1. Oak Tree
2. Bluebell
3. Dandelion
4. Fern
5. Pine Tree

1. Leaves shape:

   • If leaves are needle-like, go to 2.
   • If leaves are broad, go to 3.

2. Needle-like leaves:

   • If in clusters of two, it's a Pine Tree.
   • If in clusters of five, it's a Bluebell.

3. Broad leaves:

   • If lobed, it's an Oak Tree.
   • If heart-shaped, it's a Dandelion.
   • If feathery, it's a Fern.

1. Deer
2. Fox
3. Rabbit
4. Squirrel
5. Owl

1. Size:

   • If small, go to 2.
   • If large, go to 3.

2. Small:

   • If it has fur, it's a Rabbit.
   • If it climbs, it's a Squirrel.

3. Large:

   • If it's herbivorous, it's a Deer.
   • If predatory, go to 4.

4. Predatory:

   • If it hunts at night, it's an Owl.
   • If it hunts during the day, it's a Fox.