Topic: Food adaptation of predators, defensive adaptation of animals

Target group

8th‑grade students of elementary school

Core curriculum

General requirements

I. Knowledge of biological diversity and basic biological phenomena and processes. Pupil:

3. presents and explains the relationship between the organism and the environment.

Specific requirements

VII. Ecology and environmental protection. Student:

3. analyzes antagonistic interactions: intra‑species and interspecies competition, parasitism, predation and herbivorousness.

General aim of education

You will learn about the adaptation of animals to predation.

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• to recognize and discuss the adaptation of animals to finding food;

• to indicate features that are adaptations to defend against predators.

Methods/techniques

• activating

  • discussion;

  • brainstorming.

• expository

  • talk.

• programmed

  • with computer;

  • with e‑textbook.

• practical

  • exercices concerned.

Forms of work

• individual activity;

• activity in pairs;

• activity in groups;

• collective activity.

Teaching aids

• e‑textbook;

• notebook and crayons/felt‑tip pens;

• interactive whiteboard, tablets/computers.

Lesson plan overview

Before classes

• Students get acquainted with the content of the abstract. They prepare to work on the lesson in such a way to be able to summarize the material read in their own words and solve the tasks themselves.

Introduction

• The teacher explains the aim of the lesson and together with students determines the success criteria to be achieved.

• Students interpret the cover illustration, indicating its relationship with the subject and goals of the lesson.

• The teacher initiates a conversation introducing the topic.

  • What do you know about ...?

  • Have you ever met ...?

Realization

• The teacher presents and discusses the photo gallery. Students analyze the illustrations and answer the teacher's questions.

• Working in pairs or in small groups, pupils collect information on the adaptation of a dog (or wolf) to help him hunt. Students use abstract and online sources. The teacher designates a person who will discuss the topic. After finishing the speech, the other pupils can supplement it or ask the person referring the questions.

• Using resources from the „Animal defensive adaptations” lesson, the teacher discusses various forms of animal defense against predators..

• Using the brainstorming method, students create a list of defensive adjustments of the domestic cat and a list of its adaptations to predation. Then they compare the two letters and explain the reasons why some of the same features may help in both hunting and defense..

Summary

• The teacher asks students to carry out the recommended interactive exercise themselves.

• The teacher chooses one student by random method and asks him or her to explain in own words the meaning of a given word or concept learned during the lesson.

• At the end of the class, the teacher asks the students questions:

  • What did you find important and interesting in class?

  • What was easy and what was difficult?

  • How can you use the knowledge and skills you have gained today?

  Willing/selected students summarize the lesson.

Homework

• Listen to the abstract recording at home. Pay attention to pronunciation, accent and intonation. Learn to pronounce the words learned during the lesson.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Food adaptation of predators, defensive adaptation of animals

Meat is a high‑calorie food, therefore the animals feeding on it do not have to eat all the time and can rest a lot. Meat is also easier to digest than vegetables, which is why carnivorous animals have a less digestive systems than herbivores.

Some predators seek prey in an active way. They sneak up and kill it. Such hunting can be done alone, as in the case of most of felids. Other predators wait in hiding. Some spiders do this, constructing additional nets, as well as stingrays buried in mud. Many predators live and hunt in herds. Owing to their large numbers, they can surround and ambush the victim.

Predators have a well‑developed sensory system used to locate victims: smell, sight and hearing. Some snakes, deprived of the external ear, with poor eyesight, orientate using receptors responding to their victims’ body temperature. In this way they detect warm‑blooded animals. Echolocation is used by bats and cetaceans, while fish use the lateral line organ to detect potential food or threat.

Many predatory animals are equipped with strong and sharp nails or claws to capture and hold the game. The fangs in mammals may have a similar function. In the case of birds of prey, the beak only serves to tear the prey, never to catch or carry it. Among some groups of animals, the most important organ used for hunting is the tongue. The woodpecker's tongue is long and sharp with small teeth facing the rear. The bird slides it into the corridor hollowed by the victim in a tree, hooks it with its tongue and pulls it out. Animals such as frogs, chameleons, anteaters catch small invertebrates with a sticky tip of an extremely long tongue. Such a strategy works well with animals whose victims are numerous and tiny.

Some vertebrates swallow victims in whole. Some fish, snakes and owls do so. Digesting such a large portion of food takes a long time.

Potential victims of predators have their own ways to survive. One of them is camouflage. Many animals have camouflage colouring, allowing them to blend in with the environment in which they live. A perfect example is the Tawny frogmouth – a bird closely related to our native European nightjar. The shapes of some animals, in particular insects, e.g. stick insects and leaf insects, make them similar to parts of plants. Both herbivores and predators take up the masking colour and shape. The latter use them as a form of defence against larger carnivores.

The reverse strategy is usually used by animals whose defence is poison. They have a vivid colouration that indicates they are inedible. Insects and amphibians such as some species of salamanders and all poison dart frogs are toxic. Some defenceless species pretend to be poisonous. They are brightly coloured and resemble dangerous animals.

The aforementioned strategies of defence against predators, as turtle's armour and hedgehog spikes, are examples of passive defence. Animals can also use active defence. Bees, wasps or hornets use their stings, buffaloes attack with strong horns, mice hurt the attacker with sharp teeth, skunks spill the stinking substance on the enemy. Another way of defending oneself is to escape. The animals using this strategy have long legs and can run fast or perform sudden jumps.

Another form of defence against predators is giving birth by females living in herds at a specific time during the year. This way new‑borns (or eggs) remain the target of predator attacks only for a short period of time when they are still defenceless. Birds would suffer greater losses if they were born throughout the year, constantly providing food to predators.

• Defence adaptations increase the chance of survival.

• Animals use passive defence mechanisms (camouflage, toxins, armour or spikes) or active defence mechanisms (escape or taking a threatening posture).