Synopsis
Spec references J247: B5.2c J250: B5.2c. Clip starts with a description of hearing and then goes into the evolution of fish gills and jaw, and how reptiles' and mammals' jaws evolved.

Sea turtle conservation | A Perfect Planet
Spec references J247: B6.1b, B6.1c J250: B6.1b, B6.1c. How increasing ocean temperatures affect currents, and therefore marine animals. Conservation of sea turtles example is used in this clip, including how changing sea temperatures affect their survival.

Importance of marine protected areas | A Perfect Planet
Spec references J247: B6.1b, B6.1c, B6.1d J250: B6.1b, B6.1c. How an increase of carbon dioxide and overfishing impacts the sea ecosystem. There has been the creation of marine protected areas, trying to prevent poaching. Sharks, whales and dolphins can also accidentally get killed, for example through commercial fishing.