Blog scientist
Oceans on brink of mass extinction: study
Brain exercises delay mental decline
Meaning of life changes across cosmos
Ancient Nubians drank antibiotic beer
First mission to touch the Sun
There's gold in them thar bacteria!
Low vitamin D linked to schizophrenia
Weight loss may be toxic: study
Pilbara find points to earliest life
Researchers uncover dance moves to impress
Visual trickery key to luring lover
Scientists find short-sightedness gene
Artificial 'skin' can sense pressure
Study confirms antibiotics mess with gut
Phone chatter could power mobiles
Stowaways found hitching ride on seaweed
Fishing could feed millions more: report
Amateurs make an astronomical impact
Study reveals new piece in autism puzzle
Genome map may help devil fight cancer
Report says ozone layer depletion stopped
Moon's surface at saturation point
Gene sweeps nets female cancer clues
Australia birthplace of astronomy: study
Stowaways found hitching ride on seaweed
Scientists in New Zealand have shown for the first time that sedentary coastal creatures can travel long distances at sea by hitching a ride on seaweed.

Researchers have long thought that animals such as molluscs and sea stars, which cannot travel far under their own steam, must 'raft' from one coast to another. But so far evidence for rafting has been circumstantial.

Now a study published today in the journal Proceedings of the Royal Society B by researchers from the University of Otago in New Zealand have confirmed such a trip.

Dr Ceridwen Fraser, a zoologist at the university's Allan Wilson Centre for Molecular Ecology and Evolution, and colleagues analysed bull kelp, a monster-sized seaweed often found floating in the Antarctic Circumpolar Current of the Southern Ocean.

Genetic tests on specimens of bull kelp washed up on a beach in the country's South Island showed that the kelp must have come hundreds of kilometres from either the sub-Antarctic Auckland or Snare Islands.

Bull kelp is usually anchored to coastal rock by a strong root-like structure called a 'holdfast'. Animals can burrow into these dinner plate-sized structures, creating diverse communities, which remain when the kelp breaks off.

Tests on a type of crustacean found in the holdfasts showed that it too had come from the same islands. Along with the crustacean were molluscs, and a type of limpet, sea spider, snail and seastar.

"We can really see that this raft has come hundreds of kilometres across the ocean carrying animals and that they've survived the journey," says Fraser.

"I'm sure that this is happening all around the world. There are other types of seaweed that float in the Northern Hemisphere - it could be a major transport system for a lot of coastal animals," she adds.
Global transportation

Co-researcher Dr Jonathan Waters says the next step is to look for the phenomenon on a global scale.

"We'd really like to go and find that smoking gun of something that's gone from one side of the world to the other - from New Zealand to Chile, for example."

Bull kelp doesn't grow in Australia but it has been found on beaches so it could easily be bringing species to Australia, says Waters.

Dr Cynthia Riginos, an evolutionary biologist at the University of Queensland, describes the research as "very interesting".

"Most marine species have swimming planktonic larvae that can move across large stretches of open water - for them, long distance movements are expected."

"For organisms [such as these] where there is no swimming stage, this helps to understand how one species can be found among geographically widespread locations."

Census charts world beneath the seas
Wonder carbon nets pair Nobel Physics Prize
Focus on chest for CPR: study
Bull ants have right eye for the job
Carbon chemistry pioneers share prize
Ancient galaxies found in modern universe
Solar surprise for climate models
Study predicts end of world as we know it
Rare plant has biggest genome yet found
Astronomers find long-lost lunar rover
Flight paths may be bad for the heart
Complex Haitian quake triggered tsunamis
US doctors usher in 'dawn of stem cell age'
Changing demographics impact CO2 levels
Sleeping in lit room leads to weight gain
Harsh conditions create sterile workers
Study finds pigeons love a flutter
Humpback whale beats long-distance record
Survey to dive deep into Australian waters
Bad jobs affect mental health
Hubble captures suspected asteroid crash
Mysterious pulsar has astronomers in a spin
Native rice may hold key to food future
Future LEDs may be what the doctor orders
Bilingualism good for the brain
Organ consent needs thought transplant
Cavemen ground flour, prepped veggies
Fossilised iceblocks shed light on early life
Water on Moon bad news for astronomy
Human eye evolved to see dark world
Wind could have parted sea for Moses
CERN scientists spot potential discovery
Malaria crossed to humans from gorillas
Horny find uncovers Triceratops' predecessor
Time passes quicker for high flyers
Da Vinci's ornithopter takes flight
Software smart bomb aimed at Iran: experts
High oestrogen levels may impact brain
Quantum leap towards computer of the future
Study finds predictive power of search
Cardio routine can nurture sweet dreams
Restored Apollo 11 footage to be screened
'Extinct' animals back from the dead
Astronomers find home away from home
Study locates our sense of direction
Records reveal First Fleet's wet welcome
Dinosaurs taller thanks to thick cartilage
Free mammograms 'should start at 40'
Grunting slows opponent's reaction time
Colour preferences shaped by experience
Father of IVF wins Nobel prize
Happiness more than gene deep
Visit Statistics