Catalog Search Results
Author
Series
Life in the World's Oceans volume 5
Language
English
Description
Phytoplankton form the base of almost all marine food chains, including that of the blue whale, the largest animal known to have ever existed. But far below the penetration of sunlight, a very different and only recently discovered food web relies solely on the chemosynthetic ability of bacteria.
Author
Series
Life in the World's Oceans volume 11
Language
English
Description
Fish certainly have good reason to fear these top-of-their-game predators, with their multiple rows of teeth and ability to detect electrical current better than any other animal. But while four species have been known to assault humans with no provocation, almost 99 percent of the many hundred shark species would rather swim away from us than attack.
Author
Series
Life in the World's Oceans volume 25
Language
English
Description
Are marine mammals to be exploited as a resource? Or are they intelligent creatures to be revered with an almost religious admiration? Your answer might depend to some extent on your country and culture of origin. Our relationship with these impressive animals continues to evolve as we increase our understanding of their biology, cognition, and sociality.
Author
Series
Life in the World's Oceans volume 28
Language
English
Description
Most of us seem to have a natural instinct to want to help a stranded marine mammal, but it requires very specific skills to render aid without causing further stress and harm. Even with the best intentions and professional assistance, not all animals can be saved. What can we learn from these strandings-no matter how they end-and where are they most likely to occur?
Author
Series
Life in the World's Oceans volume 9
Language
English
Description
Through 550 million years of evolution, fish have developed a wide variety of adaptations to the unique demands of living in a watery and mostly dark world. Learn how gills, swim bladders, bioluminescence, chemosensory glands, echolocation, and electrolocation have allowed fish to succeed in almost every type of ocean environment. Which fish are our ancestors? You might be surprised.
Author
Series
Life in the World's Oceans volume 6
Language
English
Description
When we think of healthy marine ecosystems, we should be thinking about phytoplankton. In many ways, we owe our existence to these diatoms, dinoflagellates, green algae, cyanobacteria, and others. Not only do scientists believe they are the ancestors of terrestrial plants, but phytoplankton continues to produce about half of all the oxygen available in our atmosphere today.
Author
Series
Life in the World's Oceans volume 16
Language
English
Description
For all practical purposes, terrestrial mammals live on a plane. Marine mammals, on the other hand, navigate a more viscous, three-dimensional environment with all its opportunities and challenges. We understand their propulsion mechanisms fairly well. But how do they control their buoyancy to position themselves in the water column? We don't yet have the answers.
Author
Series
Life in the World's Oceans volume 24
Language
English
Description
Within their own species, marine mammals have developed sophisticated communication. In captivity, we know they can be trained to learn rules, which indicates higher cognitive function. And even in the wild, we have documented some extraordinary instances of learning and cultural transmission of information. But is their intelligence comparable to our own?
Author
Series
Life in the World's Oceans volume 26
Language
English
Description
Over and over, humans have behaved as if a given resource were inexhaustible. That was certainly the case with worldwide industrial whaling of the early 20th century, when six species of whales were hunted to dangerously low numbers. In the near future, as their populations continue to recover, some countries are expected to promote a resumption of the commercial whale hunt.
Author
Series
Life in the World's Oceans volume 12
Language
English
Description
While the reptilian evolution of the amniotic egg allowed animals to move completely from the sea onto land, some reptiles retained strong marine ties. These include sea turtles and sea birds whose wide variety of adaptations allow for drinking saltwater, remaining underwater for long periods, and flying great distances using very little energy.
Author
Series
Life in the World's Oceans volume 20
Language
English
Description
With plastic and nylon lines and nets becoming common in the last century, by-catch became an even greater problem for the marine mammals. When the media picked up the story in the mid-1960s, the public became engaged, and the Marine Mammal Protection Act was passed in 1972. But whale entanglement remains a problem, and some argue that even whaling was far less cruel.
Author
Series
Life in the World's Oceans volume 10
Language
English
Description
While humans have been fishing for hundreds of centuries, we have only recently had a significant impact on marine food webs. Industrialization has led to problems with by-catch and overexploitation of resources. Today, we are creating trophic cascades with long-term impacts we do not yet understand.
Author
Series
Life in the World's Oceans volume 14
Language
English
Description
Through tens of millions of years, evolution has resulted in a fascinating array of marine mammal adaptations. With the ability to process thousands of gallons of water each day or dive to a depth of almost three kilometers, and with numerous methods of locomotion or extraordinary social behaviors, these whales, porpoises, phocids, and more can thrive in varied environments around the globe.
Author
Series
Life in the World's Oceans volume 8
Language
English
Description
Mammals are certainly represented in ocean life, but which species should be identified as "marine" when considering ocean productivity? The extremely complex marine food webs maintain long-term stability, even as they undergo natural perturbations over time. But when Homo sapiens enters as an apex predator, productivity can deteriorate, and systems can even collapse.
Author
Series
Life in the World's Oceans volume 27
Language
English
Description
Although the irony is unmistakable, our understanding of marine mammals increased tremendously by having access to carcasses during the years of industrial whaling. Today, we focus on species protection while learning as much as we can via SCUBA, SONAR, tagging, biopsy darts, photo-identification, studying animals in captivity, and examining stranded individuals when available.
Author
Series
Life in the World's Oceans volume 4
Language
English
Description
Beach organisms exist with the constantly changing winds, waves, and tides (sometimes underwater, sometimes fully exposed to the air). Life in estuaries, where rivers meet the oceans, face constant fluctuations in environmental salinity. And hard corals are continually pummeled by wave action. Yet each of these physically challenging environments can be diverse and fecund ecosystems.
Author
Series
Life in the World's Oceans volume 13
Language
English
Description
Marine mammals did not evolve from marine species. Rather, they evolved from land mammals who found a plethora of "suddenly" open ecological niches when the dinosaurs became extinct. Today's marine mammals might resemble each other because convergent evolution has led to similar adaptation. But best as scientists can tell, they have five separate lineages and no single common ancestor.
Author
Series
Life in the World's Oceans volume 19
Language
English
Description
Two things are clear: Almost all marine food webs are based on microscopic photosynthesizers, and only a small fraction of the energy available at any trophic level becomes available to the next level. Adaptations such as baleen, ventral pleats, and unique tooth morphology allows these large animals to meet their energy needs.
Author
Series
Life in the World's Oceans volume 22
Language
English
Description
From individual whales that corral their confused prey to highly coordinated bubble-net feeding and aunts who "babysit," marine mammals have developed an extraordinary variety of social and hunting behaviors developed over millions of years. If the energy expenditure does not support the goal of passing on genetic material, natural selection will eventually drop the adaptation.
Author
Series
Life in the World's Oceans volume 23
Language
English
Description
With 60 million years of evolution on their side, marine mammals have adapted to the widest possible variety of marine ecological niches. Some live only in rivers or lakes, others only in waters over the continental shelves, and some in the open ocean. A few are even adapted to live at the poles.