Bottlenose dolphins and beluga whales accumulate more chemical pollutants in their bodies when they live and feed in waters near urbanized areas. (NOTE: Subscribers can still listen to these shows). If dolphins could talk, what would they say to us? Well, it turns out they CAN--it's just up to us to learn their language.
A diver carrying a computer that tries to recognize dolphin sounds and generate responses in real time will soon attempt to communicate with wild dolphins off the coast of Florida. This will be a major step towards two-way communication between humans and dolphins. Louis Herman of the Kewalo Basin Marine Mammal Laboratory in Honolulu found that bottlenose dolphins can keep track of over 100 different words and can also respond to simple commands. In New Scientist, MacGregor Campbell quotes Denise Herzing, founder of the Wild Dolphin Project in Jupiter, Florida, as saying, "They create a system and expect the dolphins to learn it, and they do, but the dolphins are not empowered to use the system to request things from the humans. We don't even know if dolphins have words. We could use their signals, if we knew them. We just don't."
If they DO start to communicate with us, we can guess what they'll "say"--Clean up your act! A research team looked at the levels of persistent organic pollutants (POPs) found in male dolphins along the US East and Gulf of Mexico coasts and Bermuda, while the other group examined the levels of perfluorinated compounds (PFCs) in beluga whales at two Alaskan locations. As you can imagine, they found LOTS of pollutants, affecting both species.
But maybe there won't be much need to worry about aquatic mammals soon: The mass extinction of marine life in our oceans during prehistoric times is a warning that the Earth will see such an extinction again because of high levels of greenhouse gases. This is what the Master of the Key warned Whitley about when he told him about climate change. Geologists have been studying "greenhouse oceans'"--oceans that have been depleted of oxygen and suffered from increases in carbon dioxide and temperature, using core samples drilled from the ocean bed off the coast of western Africa. They found a significant amount of organic material--marine life deposited within a 400,000 year timespan--buried within deoxygenated layers of the sediment.
Geologist Thomas Kennedy says, "Our research points to a mass mortality in the oceans at a time when the Earth was going through a greenhouse effect, with high levels of carbon dioxide in the atmosphere, and rising temperatures, leading to a severe lack of oxygen in the water that marine animals are dependent on.
"After a (low oxygen) phase, oxygen concentration in the ocean seems to improve, and marine life returns. Our results show that natural processes of carbon burial kick in. Importantly, this rescue comes from the land, with soil-formed minerals acting to collect and bury excess dissolved organic matter in seawater. Burial of that excess carbon ultimately contributes to CO2 removal from the atmosphere, cooling the planet and the ocean. This is nature's solution to the greenhouse effect and it could offer a possible solution for us. If we are able to learn more about this effect and its feedbacks, we may be able to manage it, and reduce the present rate of warming threatening our oceans."