Distinguish between external and internal fertilization and describe the different types of development (altricial, precocial, ovoviviparous). Give examples of animals for each.

• 1.5.1 External fertilisation: Fishes

Altricial young are helpless at birth and require extensive parental care.

• 1.5.2 Internal fertilisation with altricial development: Chimpanzees, Humans, Whales

Precocial young are relatively mature and mobile at birth/hatching.

• 1.5.3 Internal fertilisation with precocial development: Snakes, Chickens, Crocodiles

Viviparous animals give birth to live young.

• 1.5.4 Viviparous animals: Chimpanzees, Humans, Whales

• 2.2.1 Define ovovivipary: Ovovivipary is a reproductive strategy where embryos develop inside eggs that remain within the mother's body until they are ready to hatch. The mother provides protection but no direct nourishment after the egg is formed.

Precocial development requires more nutrients and energy in the egg.

• 2.2.2 Which ONE of the bird species (1, 2 or 3) most probably shows a precocial development reproductive strategy? Bird species 2

• 2.2.3 Explain your answer to QUESTION 2.2.2: Bird species 2 has the highest yolk percentage ($36\%$) and energy content ($1.44 \text{ kcal/g}$), and the lowest water content in its yolk ($57\%$). This indicates a richer supply of nutrients and energy for the developing embryo, allowing it to reach a more advanced stage of development (precocial) before hatching.

This corresponds to altricial development, meaning less developed at hatching.

• 2.2.4 Which ONE of the bird species (1, 2 or 3) will possibly produce offspring requiring the highest degree of parental care? Bird species 1