Revealing seaweed secrets of North Sea coastline

First ever survey of seaweed on North Sea coastline

August 2011: The first ever survey of seaweed along England's east coast began this month, thanks to The Wildlife Trusts.

ECOSYSTEM:The blue-rayed limpet lives on kelp fronds

 
The conservation organisation is working with partners to coordinate Seaweed East, a scheme that will see a team of surveyors exploring 11 locations from Essex to Northumberland. Starting at Blackwater estuary in Essex, renowned marine biologists and Seasearch divers will work with a botanist and a wild food expert, spending an intensive period of 11 days exploring the locations, including several previously unsurveyed Wildlife Trust coastal nature reserves. At each site, all species of seaweed will be recorded, and samples taken.


Hugely versatile resource
The east coast is an under-surveyed section of the UK's coastline, often due to the perception of the area being of little ecological importance. In fact, the North Sea supports two of England's largest subtidal chalk reefs. It is hoped Seaweed East will provide vital evidence of the true variety of life this area supports.

There are around 650 species of seaweed in the UK. They are a hugely versatile resource, used in food, medicines and cosmetics. Seaweeds are equally important to marine life as they are to humans, providing food and habitat for creatures, such as the blue-rayed limpet which lives on kelp fronds.

Joan Edwards, Head of Living Seas for The Wildlife Trusts, said: ‘Seaweed plays a vital part in marine ecosystems. Its health and abundance reveals a great deal about the overall health of a given environment.

We expect some surprises
‘A seaweed survey coordinated by Isles of Scilly Wildlife Trust last year recorded at least 150 species of seaweed. It greatly increased our knowledge of the marine wildlife around the area, and turned up some invasive species previously unrecorded there. We expect Seaweed East will bring similar surprises to light.'

The Wildlife Trusts are helping to fund and coordinate Seaweed East in conjunction with Seasearch, a volunteer organisation for divers to get involved with surveying the marine wildlife they encounter in the UK. Together with Shoresearch, The Wildlife Trusts' volunteer scheme to identify and record animals, plants, and habitats along our shoreline, records are being built up of the marine wildlife our seas support. This information could help to identify areas of special importance for marine life both above and below the surface.
http://www.wildlifeextra.com/go/news/seaweed-england.html

Ancient seaweed is living fossil

By Matt Walker Editor, Earth News

Verdigellas: older than we thought

Ancient seaweed that have been found growing in the deep sea are "living fossils", researchers have reported.

The two types of seaweed, which grow more than 200m underwater, represent previously unrecognised ancient forms of algae, say the scientists.

As such, the algae could belong to the earliest of all known green plants, diverging up to one billion years ago from the ancestor of all such plants.

Details of the discovery are published in the Journal of Phycology.

"The algae occur in relatively deep marine waters - 210m, which is certainly deep for a photosynthetic organism," Professor Frederick Zechman told the BBC.

"They can be found in shallower water but typically under ledges in low light.

"They appear to possess special chlorophyll pigments that allow them to utilise the low intensity blue light found at depth."

Professor Zechman of California State University in Fresno, US, sampled the seaweeds with a team of researchers based across the US and in Belgium.

The algae had previously been identified. They belong to the scientific groups, or genera, called Palmophyllum and Verdigellas.

But Professor Zechman's team is the first to study their genetic make-up, and it is this research that has revealed their startling ancestry.

Green origins
Green plants in general belong to one of two groups, or clades.

One clade includes all land plants and the green algae with the most complex structures, known as charophytes or more commonly stoneworts.

The other clade, known as the Cholorophyta, comprises all other green algae.

Most studies have sought to determine what ancient plants gave rise to the land plants and stoneworts.

But little research has been done into the origin of the other green algae.

So Professor Zechman's team collected and studied Palmophyllum algae from New Zealand waters and Verdigellas from the western Atlantic Ocean.

These algae are unusual as they are multicellular, but their individual cells do not interact with each other in any meaningful way.

Instead, single cells sit in a gelatinous matrix, which can form complex shapes such as stalks.

The scientists analysed the DNA within the nuclei and chloroplasts in the algae's cells.

Instead of belonging to the Cholorophyta, the scientists discovered that both types of algae actually belong to a distinct new group of green plants, one that is incredibly ancient.


The algae are so different that they should be assigned their own Order, a high level taxonomic group, say the scientists.

What is more, "by comparing those gene sequences to the same genes in other green plants, we have discovered that these green algae are among the earliest diverging green plants... if not the earliest diverging lineage of green plants," Professor Zechman told the BBC.

"That would put them in the ball park of over a billion years old."

Plant progenitor
The discovery could "vastly change" our view of which green plant was the ancestor to all those we see today, he says.

That progenitor of green plants is currently thought to be a single-celled plant that had a tail-like structure called a flagellum, which allows the cell to move itself in water.

But no single-celled or flagellated algae of the types studied by Professor Zechman's team have been observed, suggesting the earliest green plants may not have had flagella after all.

Professor Zechman said the previously unrecognised ancient algae could be characterised as "living fossils", even though no actual fossils of such algae are known to exist.

The algae's ability to harness low light intensities allows them to grow in deep water habitats - and that may be the key to their incredible longevity.

At such depths, plants face less stress from the actions of waves, variations in temperature and fewer herbivores that might feed on them.

Ancient seaweed is living fossil

By Matt Walker Editor, Earth News

Verdigellas: older than we thought

Ancient seaweed that have been found growing in the deep sea are "living fossils", researchers have reported.

The two types of seaweed, which grow more than 200m underwater, represent previously unrecognised ancient forms of algae, say the scientists.

As such, the algae could belong to the earliest of all known green plants, diverging up to one billion years ago from the ancestor of all such plants.

Details of the discovery are published in the Journal of Phycology.

"The algae occur in relatively deep marine waters - 210m, which is certainly deep for a photosynthetic organism," Professor Frederick Zechman told the BBC.

"They can be found in shallower water but typically under ledges in low light.

"They appear to possess special chlorophyll pigments that allow them to utilise the low intensity blue light found at depth."

Professor Zechman of California State University in Fresno, US, sampled the seaweeds with a team of researchers based across the US and in Belgium.

The algae had previously been identified. They belong to the scientific groups, or genera, called Palmophyllum and Verdigellas.

But Professor Zechman's team is the first to study their genetic make-up, and it is this research that has revealed their startling ancestry.

Green origins
Green plants in general belong to one of two groups, or clades.

One clade includes all land plants and the green algae with the most complex structures, known as charophytes or more commonly stoneworts.

The other clade, known as the Cholorophyta, comprises all other green algae.

Most studies have sought to determine what ancient plants gave rise to the land plants and stoneworts.

But little research has been done into the origin of the other green algae.

So Professor Zechman's team collected and studied Palmophyllum algae from New Zealand waters and Verdigellas from the western Atlantic Ocean.

These algae are unusual as they are multicellular, but their individual cells do not interact with each other in any meaningful way.

Instead, single cells sit in a gelatinous matrix, which can form complex shapes such as stalks.

The scientists analysed the DNA within the nuclei and chloroplasts in the algae's cells.

Instead of belonging to the Cholorophyta, the scientists discovered that both types of algae actually belong to a distinct new group of green plants, one that is incredibly ancient.


The algae are so different that they should be assigned their own Order, a high level taxonomic group, say the scientists.

What is more, "by comparing those gene sequences to the same genes in other green plants, we have discovered that these green algae are among the earliest diverging green plants... if not the earliest diverging lineage of green plants," Professor Zechman told the BBC.

"That would put them in the ball park of over a billion years old."

Plant progenitor
The discovery could "vastly change" our view of which green plant was the ancestor to all those we see today, he says.

That progenitor of green plants is currently thought to be a single-celled plant that had a tail-like structure called a flagellum, which allows the cell to move itself in water.

But no single-celled or flagellated algae of the types studied by Professor Zechman's team have been observed, suggesting the earliest green plants may not have had flagella after all.

Professor Zechman said the previously unrecognised ancient algae could be characterised as "living fossils", even though no actual fossils of such algae are known to exist.

The algae's ability to harness low light intensities allows them to grow in deep water habitats - and that may be the key to their incredible longevity.

At such depths, plants face less stress from the actions of waves, variations in temperature and fewer herbivores that might feed on them.