Mentioned the other day that I'm reading a new book on whales by Phillip Hoare. Also seeing several whale-related news items...
A pair of papers in the latest issue of Science report new findings that relate to giant filter-feeders. In today's world ocean, the largest and most charismatic species are the great whales. The huge filter-feeding mysticetes, along with their fishy homologues like the whale and basking sharks, play a major trophic role in nutrient distribution. Well, there's some history there.
One paper, a collaboration between researchers at George Mason University in Virginia and the University of Otago in New Zealand, takes a prehistorical look at the relationship between the diversity of cetaceans and that of marine diatoms. By looking at records of whale fossils and correlating it with what we know about the history of planktonic diatoms, they found a significan
t relationship - over the last 30 million years or so, the diversity of whales has corresponded closely to that of diatoms.
Perhaps not surprising, but still good to know that the changes in cetacean diversity, as reflected in the fossil record, are real and related to a factor that we can understand.
A second paper, first-authored by Oxford's Matt Friedman, examines a group of bony fish that occupied the mysticete niche during the Mesozoic. There have been some hints at the significance of large, filter-feeding pachycormid fish, but they had been known only from the
Jurassic. An example is Leedsichthys, pictured at right, which was discovered in England in 19th Century. Leedsichthys lived in the Middle Jurassic, some 170 million years ago, and reached lengths of 30 feet or more. lived in the The new paper reports on pachycormids from Asia, Europe, and North America that show the pachycormids persisted throughout the Mesozoic, up until the end of the Cretaceous. At the time of their demise, the cetaceans were almost ready to take the stage.
A pair of papers in the latest issue of Science report new findings that relate to giant filter-feeders. In today's world ocean, the largest and most charismatic species are the great whales. The huge filter-feeding mysticetes, along with their fishy homologues like the whale and basking sharks, play a major trophic role in nutrient distribution. Well, there's some history there.
One paper, a collaboration between researchers at George Mason University in Virginia and the University of Otago in New Zealand, takes a prehistorical look at the relationship between the diversity of cetaceans and that of marine diatoms. By looking at records of whale fossils and correlating it with what we know about the history of planktonic diatoms, they found a significan
t relationship - over the last 30 million years or so, the diversity of whales has corresponded closely to that of diatoms.Perhaps not surprising, but still good to know that the changes in cetacean diversity, as reflected in the fossil record, are real and related to a factor that we can understand.
A second paper, first-authored by Oxford's Matt Friedman, examines a group of bony fish that occupied the mysticete niche during the Mesozoic. There have been some hints at the significance of large, filter-feeding pachycormid fish, but they had been known only from the
Jurassic. An example is Leedsichthys, pictured at right, which was discovered in England in 19th Century. Leedsichthys lived in the Middle Jurassic, some 170 million years ago, and reached lengths of 30 feet or more. lived in the The new paper reports on pachycormids from Asia, Europe, and North America that show the pachycormids persisted throughout the Mesozoic, up until the end of the Cretaceous. At the time of their demise, the cetaceans were almost ready to take the stage.
No comments:
Post a Comment