Unlike Oceanic islands that were once part of continental landmasses, islands formed by such geological processes as volcanism contain only plants and animals that could be transported there.
The author mentions the estimated numbers of birds and coral fish species on various Oceanic islands in order to demonstrate how much knowledge about Oceanic species has been accumulated.
The narrow strips of beach on which the turtles lay their eggs are being squeezed on one side by development and on the other by the threat of rising sea levels as the oceans warm.
The oil has already reached the Gulf stream and could be distributed among all the oceans of the world through the interlinking currents of that stream.
If the Earth-Sun distance were as little as 1 percent larger, runaway glaciations on Earth about 2 billion years ago would have caused the oceans to freeze and remain frozen to this day.