Navigation Links
Scientists discover key to Christmas Island's red crab migration

One of the most spectacular migrations on Earth is that of the Christmas Island red crab (Gecarcoidea natalis). Acknowledged as one of the wonders of the natural world, every year millions of the crabs simultaneously embark on a five-kilometre breeding migration. Now, scientists have discovered the key to their remarkable athletic feat.

A three-year project conducted by a team led by the late Professor Steve Morris from the University of Bristol's School of Biological Sciences in collaboration with Professor Simon Webster from Bangor University, has discovered that hormonal changes play a significant role in enabling the crabs to make their journey.

Lucy Turner, a researcher at the University of Bristol, said: "During the wet season on the island, in November or December, and prompted by the arrival of the monsoon rains, millions of the crabs undertake an arduous breeding migration from their home on the high rainforest plateau to the ocean to reproduce. This is a journey of several kilometres - a long way when you are a relatively small land crab (less than 20cm long).

"Scientists have long been puzzled by what mechanisms enable the necessary changes to take place in the crabs' physiology to allow this journey to take place, and how they make such a dramatic switch from hypoactivity to hyperactivity."

The results of this project have proven that it is a Crustacean Hyperglycaemic Hormone (CHH) that enables the crabs to make the most efficient use of their stored energy in the muscles (glycogen) and its conversion to glucose to fuel the migration.

Professor Webster, an endocrinologist at Bangor University, added: "Their migration is extremely energetically demanding, since the crabs must walk several kilometres over a few days. During the non-migratory period, the crabs are relatively inactive and stay in their burrows on the floor of the rain forest, only emerging for a brief period at dawn, to feed. The behaviour change reflects a fundamental change in the metabolic status of the animal.

"Surprisingly, we found that hyperglycaemic hormone levels were lower in actively migrating crabs than those that were inactive during the dry season. However, studying the crabs running and walking after giving them glucose resolved the puzzle. During the dry season, forced activity resulted in a tremendous release of hormone, within two minutes, irrespective of whether glucose had been administered. However, in the wet season, the glucose completely prevented the release of the exercise-dependent hormone, showing that they were controlled by a negative feedback loop.

"Glucose levels were clearly regulating hormone release at this time. This made sense since it ensures that during migration, glucose is only released from glycogen stores when glucose levels are low, using the crabs' precious reserves of glycogen, to ensure that they can complete the migration."


Contact: Hannah Johnson
University of Bristol

Related medicine news :

1. Scientists find link in humans between nerve cell production, memory
2. Scientists Dismayed by Stem Cell Research Ruling
3. Scientists closer to finding what causes the birth of a fat cell
4. Scientists map epigenetic changes during blood cell differentiation
5. Scientists receive nearly $11 million to develop radiation countermeasures
6. Chemical system in brain behaves differently in cocaine addicts, UT Southwestern scientists find
7. Scientists Unravel Secrets of Sound Sleep
8. Scientists develop the first model for investigating the origins of testicular cancer in humans
9. Scientists develop designer protein, opening new door in cancer research
10. Scientists unravel human-ecosystem interactions
11. UCSD scientists find gas pedal -- and brake -- for uncontrolled cell growth
Post Your Comments:
Related Image:
Scientists discover key to Christmas Island's red crab migration
(Date:6/27/2016)... ... June 27, 2016 , ... ePAY ... partnership with Connance, a healthcare industry leader providing predictive analytics to optimize ... combine to provide health systems, hospitals and ambulatory surgical centers with dramatic ...
(Date:6/27/2016)... (PRWEB) , ... June 27, 2016 , ... recently ... of Eyeglasses . , Millions of individuals in the United States and Canada ... become a way to both correct vision and make a fashion statement. Even celebrities ...
(Date:6/26/2016)... Creek, Michigan (PRWEB) , ... June 26, 2016 , ... ... joined as sponsor of the 2016 Cereal Festival and World’s Longest Breakfast Table in ... in honor of the city’s history as home to some of the world’s leading ...
(Date:6/26/2016)... ... June 26, 2016 , ... PawPaws brand pet supplements ... was developed to enhance the health of felines. The formula is all-natural and is ... herbs in the PawPaws Cat Kidney Support Supplement Soft Chews are Astragalus ...
(Date:6/26/2016)... ... June 26, 2016 , ... ... have been diagnosed with endometriosis. These women need a treatment plan to not ... comprehensive approach that can help for preservation of fertility and ultimately achieving a ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... , Belgium , June 24, ... VNRX), today announced the appointment of Dr. ... Directors as a Non-Executive Director, effective June 23, ... Audit, Compensation and Nominations and Governance Committees.  As ... Futcher will provide independent expertise and strategic counsel ...
(Date:6/23/2016)... , June 23, 2016  MedSource announced ... as its e-clinical software solution of choice.  This ... best possible value to their clients by offering ... The preferred relationship establishes nowEDC as the EDC ... for MedSource,s full-service clients.  "nowEDC has long been ...
(Date:6/23/2016)... 2016 Any dentist who has made an implant ... process. Many of them do not even offer this as ... high laboratory costs involved. And those who ARE able to ... a high cost that the majority of today,s patients would ... Parsa Zadeh , founder of Dental Evolutions Inc. and inventor ...
Breaking Medicine Technology: