case study of natural selection

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Case study of Natural selection The Tammar Wallaby’s Resistance to Sodium Fluoroacetate The tammar wallaby is a small marsupial native to South and Western Australia. Due to natural selection, it has become resistant to sodium fluoroacetate.

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Case study of Natural selection. The Tammar W allaby ’s R esistance to Sodium Fluoroacetate . The tammar wallaby is a small marsupial native to South and Western Australia. Due to natural selection, it has become resistant to sodium fluoroacetate. . Sodium fluoroacetate. - PowerPoint PPT Presentation

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Page 1: Case study of Natural selection

Case study ofNatural selectionThe Tammar Wallaby’s

Resistance to Sodium Fluoroacetate

The tammar wallaby is a small marsupial native to South and Western Australia. Due to natural selection, it has become resistant to sodium fluoroacetate.

Page 2: Case study of Natural selection

Sodium fluoroacetateSodium fluoroacetate is a poisonous colourless salt used as a pesticide, commonly known as 1080. It occurs naturally in several plants native to Australia, but is usually produced synthetically. As it is highly toxic to mammals and insects, it is used by farmers to protect crops from herbivores and to control non-native species that prey on native species.

Page 3: Case study of Natural selection

Sodium fluoroacetateGastrolobium grandiflorum (Wallflower poison) is a bushy shrub endemic to Australia that contains sodium fluoroacetate.

Page 4: Case study of Natural selection

Change in environmentThe tammar wallaby originated in South Australia. Pesticide 1080 was used here and the tammar wallaby was poisoned by it. Over time, tammar wallabies migrated to Western Australia. Here, sodium fluoroacetate occurred naturally in the plants that the tammar wallaby fed on. This change in environment placed selective pressure on the marsupials. As they were regularly consuming sodium fluoroacetate they developed a resistance to it. When pesticide 1080 was introduced in Western Australia, the tammar wallabies there were not poisoned by it like the ones in South Australia, as they had become resistant to it.

Page 5: Case study of Natural selection

Distribution Current tammar wallaby range, with red marking where the species has been reintroduced.

Page 6: Case study of Natural selection

Natural selection This resistance to sodium fluoroacetate was favourable to the tammar wallabies, so those with it survived, thrived and reproduced. Their resistance was passed onto their offspring and this characteristic became more common within the species.

Page 7: Case study of Natural selection

Steps of evolution Steps of evolution of the tammar wallaby:

1. A population of tammar wallabies developed the variation of being resistant to sodium fluoroacetate.

2. The tammar wallabies with this favourable characteristic survived, thrived and reproduced.

3. Their resistance to sodium fluoroacetate was passed onto their offspring.

4. Tammar wallabies with the favourable resistance to sodium fluoroacetate become more common within the species.