Navigation Links
Migrating squid drove evolution of sonar in whales and dolphins, researchers argue
Date:9/5/2007

thed whales, the sperm whale, grows up to 60 feet long and dives to 3,000 meters - nearly two miles - in search of squid. Though poorly known because they live entirely in the deep ocean, the many species of the beaked whale dive nearly as deep. Belugas and narwhals descend beyond 1,000 meters, while members of the dolphin family - porpoises, killer whales and pilot whales, for example - all can dive below the 200-meter mark where sunlight is reduced to darkness.

According to Pyenson, who focuses on the evolution of whales, the first whales entered the ocean from land about 45 million years ago, and apparently did not echolocate. Their fossil skeletons do not have the scooped forehead of today's echolocating whales, which cups a fatty melon-shaped ball that is thought to act as a lens to focus clicking noises.

Skulls with the first hints of a concave forehead and potential sound-generating bone structures arose about 32 million years ago, Pyenson said, by which time whales presumably had spread throughout the oceans. Whales had developed underwater hearing by about 40 million years ago.

According to Lindberg, whale biologists had various theories about echolocation, including that whales developed this biosonar soon after entering the water as a way to find food in turbid rivers and estuaries. The evolution of toothed whales, however, indicates otherwise. Whales first occupied the ocean, and only later invaded rivers. Other experts have proposed that development of echolocation coincided with global cooling around 33.5 million years ago, though a mechanism was not specified.

The most convincing explanation, that echolocation allowed whales to more efficiently find food in the darkness of the deep ocean, ignores the question of evolution.

"How did the whales know there was a large supply of food down in the dark"" asked Lindberg, noting that cephalopods are the most abundant and high-energy resource in the ocean, eaten by
'/>"/>

Contact: Robert Sanders
rsanders@berkeley.edu
510-643-6998
University of California - Berkeley
Source:Eurekalert

Page: 1 2 3 4

Related biology news :

1. New tool reveals secrets of migrating cells
2. E. coli bacteria migrating between humans, chimps in Ugandan park
3. Bats prey on nocturnally migrating songbirds
4. Ancient amphibians evolved a bite before migrating to dry land
5. Squid skin reveals hidden messages
6. Squid-inspired design could mean better handling of underwater vehicles
7. Tracking sperm whales and jumbo squid
8. Ancient global warming drove early primates dispersal
9. Molecular biology fills gaps in knowledge of bat evolution
10. Same mutation aided evolution in many fish species, Stanford study finds
11. Researchers trace evolution to relatively simple genetic changes
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/23/2014)... -- Researchers have found evidence of an interaction ... increase aggressive behavior in children, especially in girls. ... children exposed to prenatal smoking will have behavioral ... said Brian Boutwell, Assistant Professor at Sam Houston ... author on the study. "One possible explanation ...
(Date:4/23/2014)... from using triclosan as an antimicrobial ingredient in soaps, ... scientists are reporting new evidence that appears to support ... Chemical Research in Toxicology , found that triclosan, ... the growth of human breast cancer cells in lab ... Choi and colleagues note that hormonal imbalances seem to ...
(Date:4/23/2014)... the family of bacteria that causes whooping cough ... surprising findings about the bacteria,s origin and evolution. ... to control this respiratory disease, which kills 195,000 ... 343 strains of the Bordetella pertussis ... last 100 years illustrates how vaccination has shaped ...
Breaking Biology News(10 mins):Genetics risk, prenatal smoking may predict behavioral problems 2In lab tests, the antimicrobial ingredient triclosan spurs growth of breast cancer cells 2Impact of whooping cough vaccination revealed 2
... many neurodegenerative diseases the neurons of the brain are ... failed attempts and much scepticism this process was finally ... treatment in some patients with stroke. But very few ... In a new highly detailed study, researchers have ...
... microbiota in a new-born baby,s gut has been linked to ... week in PLOS Computational Biology . The findings ... the body,s microbial ecosystem - in an infant can influence ... gut of a new-born baby is quickly populated by a ...
... of large-bodied mammals inhabited the "mammoth steppe," a cold and ... northern Asia and across the Bering land bridge to the ... wolves and bears were able to maintain their ranges well ... new study led by researchers at the University of California, ...
Cached Biology News:Researchers discover a missing link in signals contributing to neurodegeneration 2Early infant growth rate linked to composition of gut microbiota 2Dietary flexibility may have helped some large predators survive after last ice age 2Dietary flexibility may have helped some large predators survive after last ice age 3
(Date:1/15/2014)... "The interface is the device," Nobel laureate Herbert ... to be found at the junctures where layers ... of nanotechnology, the interfaces between layers of metal ... such high-tech favorites as spintronics, high-temperature superconductors, ferroelectrics ...
(Date:1/15/2014)... The Pittcon Organizing Committee is pleased to announce ... , an e-Journal and producer of Food Labs ... year for the co-location of Food Labs Conference to be ... the registration fee to attend the two-day Food Lab Conference, ...
(Date:1/15/2014)... January 15, 2014 Look inside the ... items for the lab, from fluid handling to instruments ... to ship when you order. , Preferred Solutions ... , from the L/S® model for precise flow control ...
(Date:1/15/2014)... and SAN JOSE, California , ... biotechnology company developing antibody-drug conjugates for cancer, today announced the ... of Directors. Dr Reynolds has over 20 years, development experience ... Officer at Seattle Genetics. "I am delighted to ...
Breaking Biology Technology:A deeper look at interfaces 2Pittcon Announces Second Year Partnership With Food Safety Tech 2Pittcon Announces Second Year Partnership With Food Safety Tech 3Cole-Parmer Begins 2014 with the Release of Preferred Solutions 2Oxford BioTherapeutics Appoints Thomas C Reynolds MD, PhD to its Board of Directors 2Oxford BioTherapeutics Appoints Thomas C Reynolds MD, PhD to its Board of Directors 3
... Sergio Lopez , 18, of Kyle, Texas , recently underwent a ... surgery to repair a broken bone in his arm that would not heal. ... device, such as a screw or plate. It,s this implantation that deterred Lopez ... , "I ...
... ,, HAIKOU CITY, China , ... CPHI ) ("China Pharma" or the "Company"), a leading,fully-integrated specialty pharmaceuticals company ... President, Ms. Zhilin Li , has,been invited to be a speaker ... Sciences Summit. , , , ...
... May 13 Repligen Corporation (Nasdaq: RGEN ... Drug Application (IND) with the Food and Drug Administration (FDA) ... deacetylase 3 (HDAC-3) inhibitor.  This is a double-blind, single ascending ... pharmacokinetic and safety profile of RG2833 in up to 40 ...
Cached Biology Technology:Texas Teen Opts for Stem Cell Therapy, Hopes of Enlisting in Military 2Texas Teen Opts for Stem Cell Therapy, Hopes of Enlisting in Military 3China Pharma Holdings, Inc. CEO to Speak at Brean Murray, Carret & Co. 2010 Life Sciences Summit 2China Pharma Holdings, Inc. CEO to Speak at Brean Murray, Carret & Co. 2010 Life Sciences Summit 3China Pharma Holdings, Inc. CEO to Speak at Brean Murray, Carret & Co. 2010 Life Sciences Summit 4Repligen Files Investigational New Drug Application with FDA for First Drug Targeting the Core Genetic Defect of Friedreich's Ataxia 2Repligen Files Investigational New Drug Application with FDA for First Drug Targeting the Core Genetic Defect of Friedreich's Ataxia 3Repligen Files Investigational New Drug Application with FDA for First Drug Targeting the Core Genetic Defect of Friedreich's Ataxia 4
Kit Components: Anti-PARP LumiGLO Chemiluminescent Substrate Immunoblot Blocking Reagent Pyronin Y Reagent Goat Anti-Rabbit IgG, HRP conjugate Double-It Reagent Film Exposure Folders Autor...
... version of Freezerworks Unlimited includes 2 clients and ... facilitates the sharing of freezers by multiple groups ... Network Client/Server version ... in monitor with 256 colors; OS 8.6 & ...
Polypropylene test tube racks, used in Thermo Forma's line of Test Tube Rack holders...
Mixing speed from 750-3200RPM, small vortexing orbit of1.0mm...
Biology Products: