Section 3: Investigating animals: hunters and the hunted

Transcription

1 Section 3: Investigating animas: hunters and the hunted

2 Contents Section 3: Investigating animas: hunters and the hunted 3 1. Observing oca ecosystems 3 2. Discussing animas in groups 4 3. Vauing experience and oca knowedge 7 2 of 9 Friday 23 September 2016

3 Section 3: Investigating animas: hunters and the hunted Section 3: Investigating animas: hunters and the hunted Key Focus Question: How can you hep pupis investigate how different iving things feed? Keywords: predators; prey; adaptations; observations; project; animas Learning outcomes By the end of this section, you wi have: used pupi observations of ecosystems and species to expore anima adaptations and behaviours provided opportunities for pupis to share their knowedge undertaken project work with your pupis. Introduction Unike green pants, which can manufacture their own food, a animas have to find and eat pants or other animas to survive. Hunting animas (predators) are adapted for finding and catching food in many ways. Animas that are hunted (prey) are aso adapted to avoid being found, caught and eaten. Pupis are often fascinated by studying feeding reationships and adaptations. In this section, we ook at ways of encouraging pupis to ask Why? questions using animas in your oca environment. We aso ook at how to structure and record pupis observations of ecosystems and species. 1. Observing oca ecosystems An ecosystem is the pattern of ife and interaction between the iving things in a specific type of pace. This coud be a pond, a stream, a hedge, a tree, a forest, a ciff-face or even a fied. It coud be as sma as ife under a rotting og or as vast as ife in an inand ake. Thinking about ecosystems doesn t have to be compicated for you and your pupis. It is sufficient if pupis spend time observing and investigating different ecosystems. They shoud get a genera idea of what eats what, reative numbers of different species and raise some questions about how different animas interact with each other. It is important to give pupis time to think of the questions they want to ask; often short discussion in sma groups wi ead to more focused questions. Case Study 1 shows how one teacher introduced her pupis to a oca ecosystem a pond. Activity 1 shows how to start ong-term observations of your oca ecosystems. 3 of 9 Friday 23 September 2016

4 Section 3: Investigating animas: hunters and the hunted Case Study 1: Investigating food chains by observing an ecosystem A primary schoo in a squatter camp on the outskirts of Nairobi, Kenya, is next to a sma natura pond. One of the teachers took her cass for a ook, see, think sow wak around the pond. They reaised from the greenish coour of the water that there must be miions of minute agae pants and thousands of threads of spirogyra making food in the sunight. They saw hundreds of tiny tadpoes, which feed on agae. What might eat the tadpoes? Sifiso had noticed about 15 shiny, britte, arvae skins (exoskeetons) cinging to the staks of reeds eft behind by new adut dragonfies. Perhaps about ten patanna frogs ived in the pond, eating dragonfy arvae and other swimming insects. A few brown water snakes had been seen and these probaby ate frogs. Ncediswa had seen a singe hawk swoop down and catch a sma snake. The teacher recorded their observations as they waked. Afterwards, back in cass, they shared ideas and the teacher wrote these observations on the board. Everyone discussed how the animas and pants were inked in a food chain. The pupis copied the fina agreed food chain diagram from the board as we as a pyramid of numbers for this ecosystem (see Resource 1: Food chain). Activity 1: Observing oca ecosystems Tak to your cass about the idea of an ecosystem. Brainstorm a ist of probabe ecosystems near the schoo (see Resource 2: Likey oca ecosystems). Divide your cass into groups and et each one seect an ecosystem to adopt and study for the rest of the year. If there is ony one suitabe ecosystem near your cassroom, everyone can study it. Organise pupis to take turns to record the observations. Encourage them to ask questions about the animas that ive there and how they might interact with each other. What types of iving things (popuations) woud they expect to find and in what numbers? What eats what? How might numbers change during the year? Record these questions and predictions for future reference. Later, make time to visit the sites with pupis, to check their predictions. This becomes an ongoing group project. Make time every few weeks for visits and reports of new information. In this way, the pupis knowedge and understanding wi grow over time in a reaxed and informa way. Groups coud keep a scrapbook or journa to record their growing understanding of the way things happen in their ecosystem. As the project progresses, think about your pupis invovement are they motivated by this activity? Do they enjoy this way of earning? 2. Discussing animas in groups Bioogists are fascinated by the way the surviva of animas depends on adaptation for successfu hunting and the avoidance of being eaten. Think of how caws and pincers 4 of 9 Friday 23 September 2016

5 Section 3: Investigating animas: hunters and the hunted have been deveoped to seize and grasp prey or frighten off predators (scorpions, crabs, cats, the preying mantis etc.). Other animas construct traps. Think of trapdoor spiders, spiders webs and ant ion pits in soft sand. Topics to discuss with pupis or ask them to find out about coud incude mimicry, camoufage, feigning death, prickes and spines, hard shes, speed, bad tastes and even poison. In this type of work, it is a good idea to start with animas that pupis can make accurate detaied observations of. Pupis can then discuss how their observations of behaviour and structure hep these species to survive as predators, prey or both. Case Study 2 and Activity 2 expore how you can make such observations in your cassroom. Pupis coud then find out about other animas if they have access to any reference books, the Internet or oca experts. Case Study 2: A tabe of adaptations Mr Somyo s cass kept (and ater reeased) an injured chameeon that the pupis had rescued from a dog in the schoo grounds. It recovered from its injury at the back of the cassroom on a branch in a vase by the window. The pupis enjoyed watching the chameeon shooting out its tongue to catch fies. Mr Somyo asked his cass these questions: How is the chameeon adapted to be a hunter? How is the chameeon adapted to avoid being eaten by other animas (hunted)? He gave them two days to think about these questions and to watch the chameeon to hep them answer the questions. He suggested that they ook at how it moved, its eyes and its behaviour when it was threatened. Some of his oder pupis made some notes on their observations. After two days, he divided his cass into groups of five/six pupis and asked each group to choose a eader. He asked the groups to discuss the questions and to draw up a ist of at east two features that hep the chameeon hunt other animas and two features that hep it avoid being eaten by other animas. He gave them 30 minutes for this discussion and during this time he went round a the groups encouraging them to use their observations about the chameeon. He aso emphasised that the group eader shoud make sure that each pupi in the group had a chance to speak. After haf an hour, each group gave one observation to the cass. Mr Somyo recorded a their observations on the board as a tabe. 5 of 9 Friday 23 September 2016

6 Section 3: Investigating animas: hunters and the hunted Activity 2: The preying mantis a successfu insect predator Preying mantises are very common in Africa. They can easiy be kept safey in the cassroom for a short whie (see Resource 3: Keeping a preying mantis in the cassroom). If fed ive insects, their hunting adaptations and feeding behaviour can be ceary observed. Keep an exercise book or arge piece of paper near to the container as a journa for everyone to write in. Pupis can record any interesting observations, descriptions of behaviour, and drawings of adaptations that hep the mantis hunt its prey. Over a few days, aow different pupis in the cass to spend time recording their observations. Questions you might give to start the pupis observing coud be: How often does it feed? What does it eat? How does it disguise itsef to catch prey? How quicky or sowy does it move? Aso, ask pupis if they can discover whether they have caught a mae or a femae preying mantis. How can they te? How are these features hepfu to the mae and femae? Encourage pupis to write questions as we as observations. Other pupis may be abe to answer the questions. In this way, pupis can buid up coective knowedge about the preying mantis. You can extend this work by catching a mae and femae preying mantis and keeping them in the same container. 6 of 9 Friday 23 September 2016

7 Section 3: Investigating animas: hunters and the hunted Some of your pupis might want to catch their own preying mantis to earn more about it. They shoud be abe to ook after it and make further observations. These pupis coud give a presentation to the cass about what they have earned. 3. Vauing experience and oca knowedge Sady, much of the oca knowedge of the natura word is in danger of being ost in modern times. It is seen to have itte or no vaue. Perhaps oca primary schoos coud take responsibiity for reviving interest by researching and recording such knowedge and understanding. Students at a teachers coege discovered that od madaa George, the man who worked as the gatekeeper, was a wonderfu resource due to his extensive knowedge of the oca natura word. But a his knowedge and understanding was in his head and woud probaby die with him. See Resource 4: Loca knowedge for exampes of some of the things we earned from him. Do you know anyone ike this? Coud they come and tak to your pupis? We need to encourage our own pupis to become naturaists. We have aready expored the vaue of giving pupis time to undertake detaied observations of ecosystems and different species Case Study 3 shows how exciting essons can be if we vaue our pupis knowedge and aow them to make decisions about their own earning. Here, the pupis were abe to show their earning to others and decide what they wanted to research further. Think about essons where you coud try this. The Key Activity uses this way of working to compie a dispay or book about animas in your oca area. The emphasis is on organising observations of adaptation and feeding patterns. Case Study 3: Learning from experience A science education ecturer was disappointed to observe a Grade 5 esson on birds that reay didn t work we. The student teacher foowed the curricuum and textbook of the time, but the pupis seemed bored. Refecting on the faiure of the esson to catch the pupis imaginations, the teacher and ecturer reaised that any three-year-od preschooer woud aready know that birds had wings, feathers and beaks and that they usuay made nests and aid eggs. Later, the ecturer and the student teacher, Ngodwane, panned a very different esson where they took in artefacts (such as bits of a broken swaow nest, assorted feathers, the discarded she of a hatched chick, a dead vuture that had been hit by a car that morning near the schoo) and pictures of oca birds. They put the items on the front bench and eft groups of pupis to choose something and te their cassmates what they knew about that thing. What coud they te us about birds? What a different esson! We coudn t stop them taking. They had so much to te. They tod us things we didn t know, ike: swaows mate for ife, raise a few broods each season, and sometimes, on dead chicks (baby swaows) thrown out of the nest, you find strange boodsucking tick-ike things that can run very fast. Pupis went on right through unchtime teing us a the interesting things they knew about oca birds and discussing their own unanswered questions. These were recorded for answering ater. 7 of 9 Friday 23 September 2016

8 Section 3: Investigating animas: hunters and the hunted Key Activity: Researching and recording oca knowedge Here, you and your pupis pan and draw up a arge tabe on a poster to record information that pupis find out about a kinds of oca animas. It coud have coumn headings such as: 8 of 9 Friday 23 September 2016

9 Section 3: Investigating animas: hunters and the hunted 9 of 9 Friday 23 September 2016