搜索结果: 1-15 共查到“理学 Sharks”相关记录18条 . 查询时间(0.049 秒)
Blue sharks use ocean eddies as fast-tracks to food(图)
Blue sharks ocean eddies fast-tracks food
2019/10/21
Blue sharks use large, swirling ocean currents known as eddies to fast-track their way to food in the twilight zone -- a layer of the sea between 200 and 1,000 meters deep, according to new research b...
Ancient Sharks Likely More Diverse Than Previously Thought(图)
Ancient Sharks More Diverse Previously Thought
2018/1/31
Sharks have a reputation as ravenous hunters and apex predators, but new analysis of fossil records shows that some of the earliest sharks might have been filter feeders, taking in water through their...
Sharks, marine scientists say, are often misunderstood, described as ravenous man-eaters. But researchers have discovered that sharks are critically important to the health of the world's oceans.For m...
Reef Fish That Conquer Fear of Sharks May Help Control Excess Algae
Reef Fish Conquer Fear Sharks Control Excess Algae
2017/2/16
If there was a top-rated restaurant in a dangerous part of the city, chances are some brave souls would be willing to risk it all for a delicious meal.
So it goes with coral reef fish dining on algae...
Proton-conducting material found in electrosensory organs of sharks
Proton-conducting material electrosensory organs sharks
2016/5/19
Sharks, skates, and rays can detect very weak electric fields produced by prey and other animals using an array of unusual organs known as the ampullae of Lorenzini. Exactly how these electrosensory o...
Protein Evolution in Different Cellular Environments: Cytochrome b in Sharks and Mammals’
Cellular Environment Sharks and Mammals’
2015/12/17
DNA sequences for the mitochondrial cytochrome b gene were determined for 13
species of sharks. Rates and patterns of amino acid replacement are compared for
sharks and mammals. Absolute rates of ...
The truth about sharks
truth sharks
2015/8/4
Danger: shark attack (or more properly, say scientists, shark bite). With sharks swimming ever closer to shore this summer--or seeming to--and crossing paths with surfers and bathers, what's going on?
Rapid Subsurface Ocean Warming in the Bay of Fundy as Measured by Free-Swimming Basking Sharks
Measured Free-Swimming Basking Sharks
2015/7/17
It is widely recognized that the western North Atlantic has recently warmed very rapidly. Sea surface temperatures (SST) in 2012 were measured to be 1–3°C higher than the 1982–2011 average (Mills et a...
Chasing Science At Sea: Racing Hurricanes, Stalking Sharks, and Living Undersea with Ocean Experts
Racing Hurricanes Stalking Sharks
2015/7/3
All marine scientists who work in the field have them—personal stories of amazement, discovery, awe, excitement, and even danger while conducting research. They are the stories we love to tell to frie...
Sharks sense prey in surprising ways during pioneering study
Sharks sense prey in surprising ways during pioneering study
2014/4/16
A team of scientists have unmasked the intricacies of how sharks hunt prey — from the first whiff to the final chomp —in a new study about shark senses that was supported by the National Science Found...
Great white sharks—top predators throughout the world's ocean—grow much slower and live significantly longer than previously thought, according to a new study led by the Woods Hole Oceanographic Insti...
Contribution of Eocene sharks and rays from southern France to the history of deep-sea selachians
SW France Eocene Deep-sea selachians Fossil record
2009/10/20
Fossil deep-sea selachians are rare and their diversity underestimated as a consequence of the scarcity of available outcrops of sediments containing them. Here we report a new fossil locality from th...
Anew species of extinct bullhead sharks,Paracestracion viohli sp. nov.(Neoselachii, Heterodontiformes),from the Upper Jurassic of South Germany
Heterodontidae Late Jurassic Schamhaupten Diversity
2009/10/20
The early history of heterodontid sharks is documented mainly by isolated teeth. So far, three different heterodontid genera have been recorded from the Jurassic: Proheterodontus from theMiddle Jurass...
Interrelationships of Mesozoic hybodont sharks as indicated by dental morphology preliminary results
Hybodont sharks Tooth morphology Dentition Mesozoic Phylogeny
2009/10/20
As many hybodont sharks are known solely from their teeth, this investigation approaches the phylogeny of the group with an emphasis on tooth morphology and dentitional patterns. The preliminary resul...
Mesozoic hybodont sharks from Asia and their relationships to the genus Ptychodus
Jurassic Cretaceous Hybodontiformes Ptychodontidae Asia
2009/10/20
The affinities of the selachian genus Ptychodus is discussed and Hemiptychodus is here re-introduced as a subgenus characterized by unusual tooth ornamentation pattern.An overview ofAsian hybodont gen...