Activi | Achieve! ] Adaptation BACKGROUND ‘habitat (say nab-tat’) the particular place where a group of living things live ‘marsupial (say ‘marr-soup-ee-al’) - a type of small furry mammal, with a pouch for its young species (say’spee-seas) - a group of living things that can breed together to produce fertile offspring Adaptation is the name that scientists give to the way that living things change and become better suited to their habitats. Offspring are not identical to either of their parents. Each new generation of a species isa tiny bit different from the one before. The theory of evolution says that these tiny differences are not noticeable from generation to generation, but over thousands or millions of years these small differences can completely and obviously change the way a plant or animal looks or functions. Adaptation results in new species and new subspecies. In this way it contributes to the biodiversity, or biological diversity, of life on Earth. ES 1 Explain why you think offspring are not identical to either of their parents. tions within a species. The process of adaptation happens because of small vai Variations that give some individuals a better chance of survival than other individuals in their species lead to what we call ‘survival of the fittest; or natural selection. An example of a variation that might give a better chance of survival is a different fur colour, which might make it easier for a small animal to hide from predators. Because the changed individuals are more likely to survive, they are more likely to breed and produce offspring, Their offspring are more likely to have the changed feature, or trait. Over time, this can result in a complete change to all the individuals in a species, The new species trait is called the adaptive trait, or the adaptation. © Ally Churley and Blake Education 2014 ACHIEVE! Science- Ecosystems 53Adaptation cont’p 2 Add the missing vowels (a, e, i, 0, u) to complete the following words. Hint: All the Activity sheet - Plant and animal biodiversity Achieve! | words have been used on the previous page, in this order. a) dpttn b) spes ) vrtns d) srw e) prdtrs f) ffsprng g) trt The circumstances within an ecosystem can determine whether a small variation within a species is of benefit or not. For example, within one species of small marsupial in a woodland there are slight variations in fur colour, but most have quite dark fur. Over time, the climate of the forest changes and there is more and more snow. Marsupials that have light-coloured fur are able to escape from predators more often than marsupials with darker fur. So more marsupials with light-coloured fur survive to reproduce, and they reproduce offspring that are more likely to have lighter fur. Over many generations, the species of marsupial in the woodland changes to become white-furred marsupials. 3. Are the following statements about the example adaptation true or false? a) Marsupials with light-coloured fur can run faster in the snow. True False b) Marsupials with light-coloured fur can hide better in thesnow. True False ©) Adaptation resulted in two species of marsupials, one light True False and one dark. d) The change happened quickly but it wasn't permanent. True False e) The circumstances in the ecosystem determined which True False lividuals were best suited to survive. 54 ACHIEVE! Science Ecosystems © Ally Chumley and Blake Education 2014Activity sheet - Plant and animal biodiversity | Achieve j Natural selection BACKGROUND genes (say jeans) - information carried in a living thing’ cells that determines some of its characteristics Natural selection is the term we give to the way in which a particular animal or plant survives to breed. Natural selection results in species adaptation. Evolutionary scientists call this process evolution by natural selection. Some animals within a species - a group of rabbits, for example - will be healthier, stronger and quicker than others. If this group of rabbits were to be chased by a wolf ora fox, the fittest’ ones would survive to breed because they could run faster and for longer periods of time. These better-adapted rabbits would eventually have babies, and most of the young rabbits might also inherit their parents’ strength and fitness. Over time, the less fit rabbits would die out and the stronger, fitter, faster rabbits would survive. Nature is ‘selecting’ those rabbits to be the ones that pass their genes down toa new generation. ES 1 Complete this sentence, using your own words. The word ‘fittest’ means . 2. Use just one word from the box to fill the spaces, and complete the passage. diseases babies parents _—_—_rabbits The of the ‘fittest’ creatures will be more likely to survive to have of their own. It is highly likely that those will inherit the stronger’ features of their parents. They will also probably pass those genes on to their own - There will be less and less individuals with ‘weaker’ features, as those with ‘stronger’ features (i dominate. The ‘weaker’ individuals will die out and only the fittest’ will remain. © Ally Chumley and Blake Education 2014 ‘ience- Ecosystems 55Activity sheet - Pla Achiev J Natural selection cont’p 3 Which of these rabbits show features that would most likely be’selected’ and help a group of rabbits survive? Circle your choices. a) this small, weak male rabbit loses contests with stronger male rabbits to mate with a female b) this rabbit with white fur is able to hide better in its snowy habitat than a rabbit with dark fur ©) this pet rabbit is chased by a dog and is killed d) this rabbit is able to run faster than another when it is being chased by a wolf e) this rabbit becomes blind f) this rabbit is healthier than others and is able to survive through a drought g) this rabbit fails to build itself a burrow before a snowy winter sets in hy this rabbit population has larger teeth that allow the rabbits to chew thicker, more nutritious grass than other smaller-toothed rabbits i) this male rabbit has shorter fur that allows it to stay cooler in its hot desert habitat than furrier rabbits j) this group of rabbits has chosen to live in an area that is a popular hunting ground where people come to shoot rabbits k) this rabbit's family built a better network of burrows than another group I) this pet rabbit refuses to eat vegetables or plants of any kind m) this rabbit has its burrows in an area where foxes begin to roam n) this rabbit has immunity to a disease that kills other rabbits 0) this rabbit has fur patterns that make it less attractive to mating partners than other rabbits 56 ACHIEVE! Science - Ecosystems © Ally Chumley and Blake Education 2014