Living Together: Symbiotic Relationships
The relationship between some of the algae and animals living in a coral reef is symbiotic, meaning the two species live together. Symbiotic relationships between residents of coral reefs or other communities can be mutually beneficial, but that is ...
Survivors: Predators and Prey
The ocean provides home to a dazzling variety of life. Yet there was a time when early life forms faced a multitude of struggles that threatened their ability to survive. The evolution of adaptations to overcome these challenges enabled life to endu...
Food for Thought: Primary Productivity, Carbon Dioxide and the Role of Humans
Excessive amounts of nutrients applied to lawns, agricultural fields and farms can lead to what scientists call nuisance blooms of algae. When that matter decomposes and sinks into the deeper layers of the coastal ocean, it uses up the available oxy...
Food for Thought: Conditions Required for Photosynthesis
The first step in the primary production process is photosynthesis. It can only take place if certain critical conditions are met, including the presence of light and chemical nutrients. Temperature also plays a role, with reactions proceeding more ...
Life Goes On: Vertebrates: Marine and Terrestrial
Marine biologists informally classify marine animals into two large groups: invertebrates and vertebrates. Vertebrates have backbones, while invertebrates do not. There are far more invertebrates than vertebrates in the ocean, but the vertebrates-wh...
Survivors: Long-Term Survivors
Despite the challenges of long-term survival on Earth, some phyla-including sponges, jellyfish, arthropods and mollusks-have endured for hundreds of millions of years, even in the most extreme environments.
Survivors: Early Invertebrates
The first animals on Earth were invertebrates-animals without backbones-and they diversified rapidly in the geologic period known as the Cambrian.