4. Adaptations

Question 1

Importance of adaptations

Answer 1

• Being adapted to an env means an organism has features that increase its chances of survival & reproduction, & also the chances of its offspring reproducing successfully.
• The features are called adaptations, can be behavioural, physiological & anatomical.

Question 2

Why do adaptations develop

Answer 2

Adaptations develop bc of evolution by natural selection.

In each generation, the best-adapted individuals are more likely to survive & reproduce - passing their adaptations on to their offspring. Individuals that are less well adapted are more likely to die before reproducing.

Question 3

What can adaptations be

Answer 3

• Behavioural
• Physiological
• Anatomical

Question 4

Behavioural adaptations

Answer 4

• Ways an organism acts that increase its chance of survival. For eg:
  
  • Possums sometimes ‘play dead’ - if being threatened by predator to escape attack, increasing chance of survival.
  • Scorpions dance before mating - makes sure they attract a mate of same species, increasing likelihood of successful mating.

Question 5

Physiological adaptations

Answer 5

• Processes inside an organism’s body that increase its chance of survival. For eg:
  
  • Brown bears hibernate - they lower their rate of metabolism over winter. This conserves energy, so they dont need to look for food in months when it’s scarce, increasing chance of survival.
  • Some bacteria produce antibiotics - to kill other species of bacteria in area. Meaning there’s less competition, increasing chance of survival.

Question 6

Anatomical (structural) adaptations

Answer 6

• Structural features of an organism’s body that increase its chance of survival. For eg:
  
  • Otters have a streamlined shape - making easier to glide through water. Makes it easier to catch prey & escape predators, increasing chances of survival.
  • Whales have a thick layer of blubber - helps keep them warm in cold sea. Increases chance of survival in places where their food is found.

Question 7

What organisms may have similar features

Answer 7

Organisms from different taxonomic groups may have similar anatomical features. (eg. whales & sharks).

Question 8

Why might organisms from diff taxonomic groups have similar anatomical features

Answer 8

Usually bc the organisms have evolved in similar environments & to fill similar ecological niches.

Question 9

What is an ecological niche

Answer 9

The role of an organism within its habitat. eg. what it eats, when/where it feeds.

Question 10

Eg for organisms in diff taxonomic groups that have similar features

Answer 10

• Most mammals are placental mammals, which develop a placenta during pregnancy & are born relatively fully developed.
• Some mammals are marsupial mammals, which dont develop a full placenta - born early in their development & climb into mother’s pouch.
• Marsupial moles & placental moles share SIMILAR ANATOMICAL FEATURES (look alike).
• However, they arent closely related - they evolved independently on diff continents. They look similar bc they’ve both evolved to live in similar envs.

Question 11

What is convergent evolution

Answer 11

When 2 species evolve similar characteristics independently of one another (bc they’ve adapted to live in similar envs) its called convergent evolution.