Monday, 5 December 2011
- Like animals, plants also need to protect themselves from their enemies.
- The enemies of plants are humans or animals that harm or eat the plants.
- Special characteristics that protect plants from their enemies include:
( a ) thorns and spines
( b ) fine hairs
( c ) the thick, hard skin of the friut
( d ) the bad smells of flowers and fruit
( e ) poison
( f ) latex
( g ) bitter fruit
- Some plants have thorns or spines on their leaves, stems or friut. These plant parts can injure enemies who go near or try to eatthe plants.
( a ) The durian friut is covered with sharp thorns.
( b) The surface of a plant is covered by sharp spines.
( c ) There are thorns on the stem of the Mimosa plant. The plant closes its leaflets when touched by its enemies. This exposes its thorns.
( d ) There are also thorns on the stems of the rose, bougainvillea and rattan plants.
- Some plants have fine hairs on their leaves, stems of fruit. The fine hairs can cause itchiness in the plants’ enemies.
( a ) The lalang grass, bamboo plant, and sugarcane plant have fine hairs on their leaves.
( b ) The bamboo plant also has fine hairs on its stem.
- The coconut and rubber plants produce fruits with thick and hard skin. This makes it difficult for animals to chew or break open the fruits. So most animals learn to avoid the fruits.
- Some plants produce flowers or fruits with bad smells. Bad smells keep animals and humans from going near the plants.
( a ) The petai fruit has a bad smell. This helps to keep animals that want to eat it away from the plant.
( b ) The Lantana flower ( bunga tahi ayam ) has a bad smell too. This keeps away enemies who want to pick or eat it.
- Some plants produce poison. The poison can make enemies who eat the plants sick or die. Examples of such plants are certain types of wild mushrooms.
- Papaya, jackfruit and rubber trees can produce latex in their stems, leaves or fruits. The latex can cause itchiness. This keeps animals that want to eat the fruits of these trees away.
- Besides physical characteristics, some animals also behave in special ways to protect themselves from their enemies. These include
( a ) changing the colour of fur or skin
( b ) living in groups
( c ) pretending to be dead
( d ) breaking off a body part
( e ) giving off a bad smell or black ink
( f ) running or flying away
( g ) hiding
- The Arctic fox can change the colour of its fur to match the colour of its surroundings.
( a ) In spring and summer, the Arctic fox has grey fur. Before the start of autum and winter, its fur will change to white.
( b ) By changing the colour of its fur, the Arctic fox can avoid being detected by its enemies easily.
- Chameleons can change their skin colour to match the colour of their surroundings, for example the colour of a tree trunk. This ability helps chameleons to hide from their enemies.
- Elephants, deer, buffaloes and zebras live and move from place to place in groups ( herds ). This allows them to defend themselves together when they are in danger.
- For example, when an enemy attacks a herd of elephants, the elephants will form a circle and keep their young in the center of the circle.
- A gecko can break off its tail when it’s enemy and gives the gecko time to escape.
- The squid and octopus can give off black ink that darkens the water around them. This can confuse their enemies and give the squid and octopus time to escape.