Tree of Life
Plant Flower, Tree
Invertebrate Octopus, Ant, Bee, Butterfly, Spider, Lobster
Vertebrate Fish, Seahorse, Ray, Shark, Frog, Turtle, Tortoise, Dinosaur
Bird, Ostrich, Owl, Crow, Parrot
Mammal Bat, Rabbit, Giraffe, Camel, Horse, Elephant, Mammoth
Whale, Dolphin, Walrus, Seal, Polar Bear, Bear, Cat, Tiger, Lion, Dog, Wolf
Monkey, Chimpanzee, Human
These are organized by a classification scheme developed exclusively for Cosma. More…
dolphin : any of various small marine toothed whales (family Delphinidae) with the snout more or less elongated into a beak and the neck vertebrae partially fused
Note: While not closely related, dolphins and porpoises share a physical resemblance that often leads to misidentification. Dolphins typically have cone-shaped teeth, curved dorsal fins, and elongated beaks with large mouths, while porpoises have flat, spade-shaped teeth, triangular dorsal fins, and shortened beaks with smaller mouths. — Webster
Dolphins are a widely distributed and diverse group of aquatic mammals. They are an informal grouping within the order Cetacea, excluding whales and porpoises, so to zoologists the grouping is paraphyletic. The dolphins comprise the extant families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the new world river dolphins), and Pontoporiidae (the brackish dolphins), and the extinct Lipotidae (baiji or Chinese river dolphin). There are 40 extant species of dolphins. Dolphins, alongside other cetaceans, belong to the clade Cetartiodactyla with even-toed ungulates. Their closest living relatives are the hippopotamuses, having diverged about 40 million years ago.
Dolphins range in size from the 1.7 m (5.6 ft) long and 50 kg (110 lb) Maui’s dolphin to the 9.5 m (31 ft) and 10 t (11 short tons) killer whale. Several species exhibit sexual dimorphism, in that the males are larger than females. They have streamlined bodies and two limbs that are modified into flippers. Though not quite as flexible as seals, some dolphins can travel at 55.5 km/h (34.5 mph). Dolphins use their conical shaped teeth to capture fast moving prey. They have well-developed hearing which is adapted for both air and water and is so well developed that some can survive even if they are blind. Some species are well adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water.
Although dolphins are widespread, most species prefer the warmer waters of the tropic zones, but some, like the right whale dolphin, prefer colder climates. Dolphins feed largely on fish and squid, but a few, like the killer whale, feed on large mammals, like seals. Male dolphins typically mate with multiple females every year, but females only mate every two to three years. Calves are typically born in the spring and summer months and females bear all the responsibility for raising them. Mothers of some species fast and nurse their young for a relatively long period of time. Dolphins produce a variety of vocalizations, usually in the form of clicks and whistles. — Wikipedia
Dolphins and Whales News -- ScienceDaily Whales and dolphins. Whale songs, beaching, endangered status -- current research news on all cetaceans.
Technique allows dolphin pregnancy exams to...
on January 10, 2020 at 6:54 pm
In a groundbreaking study, scientists have developed a new ultrasound technique for evaluating dolphin fetuses at all stages of gestation.
A 'pivotal' moment for understanding whale...
on January 9, 2020 at 3:08 pm
We could be getting closer to understanding how feeding behaviors in whales and dolphins have evolved over time.
Consider marine life when implementing offshore...
on December 17, 2019 at 4:42 pm
With countries adopting green energy practices, renewable energy now accounts for a third of the world's power. As this trend continues, more countries are looking to offshore energy sources to produce this renewable energy. Researchers identify situations where green technology such as wind turbines, wave energy converters, and other marine renewable energy devices (MREDs) have had negative consequences on marine life.
Resident orcas' appetite likely reason for...
on December 16, 2019 at 8:14 pm
Large, old Chinook salmon have mostly disappeared from the West Coast. A new study points to the recent rise of resident killer whales, and their insatiable appetite for large Chinook salmon, as the main driver behind the decline of the big fish.
The limits of ocean heavyweights: Prey curb...
on December 12, 2019 at 7:26 pm
Scientists collected data from hundreds of feeding whales, allowing them to determine how much energy species of different sizes invest to capture their prey and which of these species reap the greatest rewards for their efforts. Their findings reveal that body size in all whales is limited by the availability of their prey, but only filter-feeding whales have evolved a feeding strategy that drives them to achieve the largest body sizes to have ever evolved.
Phys.org - latest science and technology news stories Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine.
Technique allows dolphin pregnancy exams to...
on January 10, 2020 at 6:36 pm
Ultrasound has been used for decades to study dolphin health and much of that work has been pioneered by veterinarians at the National Marine Mammal Foundation (NMMF). But in a groundbreaking study just published in Veterinary Radiology & Ultrasound, scientists have developed a new ultrasound technique for evaluating dolphin fetuses at all stages of gestation. This recent advancement in dolphin medicine allows veterinarians to evaluate dolphin pregnancies the same way doctors approach […]
River people: Life along Asia's key waterways
on January 10, 2020 at 9:20 am
From the flood-ravaged banks of the Brahmaputra to the disappearing wetlands of the Mekong, Asia's main waterways—and the people that live along them—are fighting for survival.
The 97 kms between China and mastery of the Mekong
on January 10, 2020 at 8:22 am
Ninety-seven kilometres of rocks in Thai waters stand between Beijing and dominance over the Mekong, a mighty river that feeds millions as it threads south from the Tibetan plateau through five countries before emptying into the South China Sea.
Prosocial and tolerant parrots help others to...
on January 9, 2020 at 5:23 pm
Parrots are considered extraordinarily clever animals. Alex, the famous Harvard-based African grey parrot, communicated with a vocabulary of more than 500 human words, could answer questions and classify objects spontaneously. Scientists from the Max-Planck-Institute for Ornithology based at the research station outpost for parrot comparative cognition in the Loro Parque in Tenerife, Spain, have shown that parrots exhibit a high level of social intelligence and cooperativeness. They readily […]
Shark and ray vision comes into focus
on January 9, 2020 at 8:31 am
Vision is a crucial sense for most animals, and vertebrates have evolved a highly adaptable set of opsin genes that generate light-sensitive pigments to decode the retinal image. These opsins include a rod opsin to help see in low light, and four classes of cone opsins to see in bright light and detect colors across the visible light spectrum.