California's Ancient Kelp Forest

The kelp forests off southern California are considered to be some of the most diverse and productive ecosystems on the planet, yet a new study indicates that today's kelp beds are less extensive and lush than those in the recent past.

The kelp forest tripled in size from the peak of glaciation 20,000 years ago to about 7,500 years ago, then shrank by up to 70 percent to present day levels, according to the study by Rick Grosberg, professor in the Department of Evolution and Ecology and the Center for Population Biology at UC Davis, with Michael Graham of the Moss Landing Marine Laboratory and Brian Kinlan at UC Santa Barbara.

Kelp forests around offshore islands peaked around 13,500 years ago as rising sea levels created new habitat and then declined to present day levels. The kelp along the mainland coast peaked around 5,000 years later.

This transition from an extensive island-based kelp system to a mainland-dominated system coincided with conspicuous events in the archaeological record of the maritime people in the region, suggesting that climate-driven shifts in kelp ecosystems impacted human populations that used those resources.

Understanding the past history of a population is crucial to understanding its genetics in the present, Grosberg said.

"Kelp is interesting because it disperses only over short distances," Grosberg said. "Populations can become genetically isolated from one another even if they are quite close together."

"We wanted to know how connected the coastal kelp populations were since the last glacial maximum," he said.

On land, scientists can reconstruct the history of a forest or grassland from fossilized pollen or leaves. But kelp do not make pollen, and marine sediments do not preserve a good record of the plants.

The researchers used depth charts of the southern California coastline and information from sediment cores on past nutrient availability to reconstruct potential kelp habitat as sea levels changed over the last 20,000 years.

"We could reconstruct changes in kelp cover at a scale of 500 years and determine how fragmented or connected the populations were," Grosberg said.

People have lived off the produce of kelp forests when resources on land dwindled, and those changes are recorded in shell middens and other traces. That archaeological record can now be compared with the ecological history to get a more complete picture of California's coast.

"Now we know what was happening with kelp, what was happening with the ecology on land, and what the people were doing," Grosberg said.

The study was published online Oct. 21 in the journal Proceedings of the Royal Society B.

Source - UC Davis

A motley collection of boneworms

It sounds like a classic horror story - eyeless, mouthless worms lurk in the dark, settling onto dead animals and sending out green "roots" to devour their bones. In fact, such worms do exist in the deep sea. They were first discovered in 2002 by researchers at the Monterey Bay Aquarium Research Institute (MBARI), who were using a robot submarine to explore Monterey Canyon. But that wasn't the end of the story. After "planting" several dead whales on the seafloor, a team of biologists recently announced that as many as 15 different species of boneworms may live in Monterey Bay alone.

After years of study, the researchers have begun to piece together the bizarre story of the boneworms, all of which are in the genus Osedax. The worms start out as microscopic larvae, drifting through the darkness of the deep sea. At some point they encounter a large dead animal on the seafloor. It may be a whale, an elephant seal, or even the carcass of a cow that washed out to sea during a storm. Following chemical cues, the tiny larvae settle down onto the bones of the dead animal.

Once settled, the boneworms grow quickly, like weeds after a rain. One end of each worm develops feathery palps, which extract oxygen from seawater. The other end of the worm develops root-like appendages that grow down into the bone. Bacteria within these roots are believed to digest proteins and perhaps lipids within the bones, providing nutrition for the worms.

Soon the worms become sexually mature. Strangely enough, they all become females. Additional microscopic larvae continue to settle in the area. Some of these larvae land on the palps of the female worms. These develop into male worms. But they never grow large enough to be seen by the naked eye. Somehow these microscopic male worms find their way into the tube that surrounds the female's body. Dozens of them share this space, not eating at all, but releasing sperm that fertilize the female's eggs. Eventually the female worm sends thousands of fertilized eggs out into the surrounding water, and the cycle begins again.

Dr. Robert Vrijenhoek, an evolutionary biologist at MBARI, has been fascinated with these worms ever since he and his colleagues first discovered their unusual lifestyles and bizarre reproductive habits. Vrijenhoek has been trying to find out how widespread and genetically diverse these worms are. He would also like to know how they manage to find and colonize the bones of dead whales in the vast, pitch-black expanse of the deep seafloor.

Between 2004 and 2008, Vrijenhoek's research team towed five dead whales off of Monterey Bay beaches and sank them at different depths within Monterey Canyon. Every few months, coauthor Shannon Johnson and others on the team would send one of MBARI's remotely operated vehicles (ROVs) down to study the worms and other animals that had colonized the whale carcasses.

To their surprise, the different whale carcasses yielded different types of boneworms. One whale carcass hosted three or four different types of worms. After examining all of the worms, coauthor Greg Rouse concluded that most of them were entirely new to science. The researchers also discovered that the worms would colonize cow-bones placed on the seafloor, which showed that the worms were not limited to feeding on dead whales.

In their recent paper in the journal BMC Biology, Vrijenhoek and his coauthors describe the results of extensive DNA analyses on all the different types of Osedax worms that have been discovered so far (including two species found off Sweden and Japan). This work suggests that these worms could belong to as many as 17 different species, most of which have yet to be named. None of the worms appear to interbreed, despite the fact that some of them grow side by side.

Based on their appearance and similarities in their DNA, the researchers divided the boneworms into several groups. Some of the worms have feathery palps, which may be red, pink, striped, or even greenish in color. Others have bare palps. One type of boneworm has no palps at all. Its body forms a single, long, tapering tube, which curls at the end like a pig's tail. This worm has evolved to live in the seafloor sediment near a dead whale. It sends long, fibrous "roots" into the mud, presumably in search of fragments of bone on which to feed.

Knowing how fast the DNA of these worms changes (mutates) over time, the researchers can calculate how long it has been since worms in the genus Osedax first evolved as a distinct group. Using one possible estimate of mutation rates, the researchers hypothesized that this group could have evolved about 45 million years ago - about the time the first large open-ocean whales show up in the fossil record. Alternatively, the worms may have evolved more slowly, which would suggest that the genus is much older, and first evolved about 130 million years ago. If this second estimate is correct, the worms could have feasted on the bones of immense sea-going reptiles during the age of the dinosaurs.

Eventually the researchers will give all these new worms their own species names. First, however, they must collect enough samples of each possible species for additional laboratory analysis and distribution to type-specimen collections. Like a classic horror story, the macabre saga of the boneworms will continue to thrill marine biologists for years to come.

This research was sponsored by the David and Lucile Packard Foundation.

Via - Monterey Bay Aquarium Research Institute

Discovery in worms points to more targeted cancer treatment

Researchers at Queen's University have found a link between two genes involved in cancer formation in humans, by examining the genes in worms. The groundbreaking discovery provides a foundation for how tumor-forming genes interact, and may offer a drug target for cancer treatment.

"When cancer hijacks a healthy system, it can create tumors by causing cells to divide when they shouldn't," says Ian Chin-Sang, a developmental biologist at Queen's and lead researcher on the study. "Certain genes control the normal movement and growth of cells, and by studying how these genes interact, we can understand what is abnormal when cancer is present."

There is an important gene in humans called PTEN that acts as a tumor suppressor. When the PTEN gene function is lost, it can lead to cancers. For example, 70-80 per cent of all prostate cancers have lost PTEN function. Another gene family, called Eph receptors, often shows high levels in cancers, but a connection between PTEN and Eph Receptors in cancer formation has never been shown. The Queen's study shows the remarkable relationship between these genes in worms.

When the research team increased Eph receptor levels in worms, the PTEN levels diminished and the worms died prematurely. When they decreased the Eph receptor level in the worm, the PTEN levels went up and the worm lived longer than normal. The team believes the same principals are applicable to humans.

"Obviously humans and worms look very different," states Professor Chin-Sang, "but at a molecular level, they are very similar. In some instances, like the ones we are studying, the cellular mechanisms are so similar that the human genes can replace the worm's gene."

The next step is to take a closer look at the interaction of these two genes in humans. The findings could lead to exciting breakthroughs in cancer treatment.

"There is a drug used in the treatment of breast cancer that some women develop a resistance to," adds Professor Chin-Sang. "Those same women have also lost their PTEN. Perhaps their Eph is overactive, and that has made the PTEN go down. The research on the worm may therefore provide a useful drug target for therapeutic intervention of breast cancer. In fact, this worm is becoming a bit of a scientific celebrity. Studies on this worm have won researchers three Nobel prizes in the last seven years."

Source - Queens University

A human being before a Prophet

By El-Sayed M. Amin

Apart from seeing Prophet Muhammad (peace be upon him) as the Messenger of God gifted with divine revelation, one can remarkably see him as an ideal example of a perfect human character.

Prophet Muhammad is a person who strove hard for the well-being of his community and of humanity at large. His farsightedness and ability to correctly read events of his time and to anticipate results helped him, along with divine wisdom from God, to address people's emotions and to win their hearts before their minds. His human touch was inescapable, and his personal appeal and gentle approach won the hearts of enemies before those of friends.

In short, he always found his way to his target audience. His cousin and Companion Ali is reported to have asserted this distinctive aspect of the Prophet's character:

The Prophet (peace be upon him) used to win the hearts of his Companions with his kind approach. He was never harsh or hardhearted. In his meetings, he used to treat all equally; listening to them all and giving all equal chance to participate in the ongoing discussions. He was a very patient negotiator, and he never withdrew himself from the discussion unless the negotiators themselves leave first. Whenever someone asked him for something, he was keen to fulfil his wish. If not, then he will please his heart with kind words. Among people, he was known by good manners and to them all he was like an affectionate father.

Missed by Friends When Absent

A man like Muhammad was the solace to his friends' souls. They would miss him very much if he went to mind personal matters, even if for a short while. This is the feeling you might have when your soul mate is absent; you always wait in anticipation for him or her to come back. That was the case with the Companions and Prophet Muhammad.

Abu Mohammad Al-Hussein Al-Baghawi in his Ma`alim At-Tanzeel (Landmarks of Revelation) mentions that Thawban, one of the Companions who showed this real love, once came to the Prophet with sadness portrayed on his face. Upon seeing him, Muhammad inquired about this noticeable sadness and very pale face.

This reflects how close the Prophet was to his friends and Companions. He would even ask about these things that we may consider trivial or unnecessary. Thawban replied,

O Messenger of God, I do not suffer from any disease. When our daily meetings come to an end, I miss you a lot until we meet the next day. Now, I remember the Last Day where you will be granted a very special status along with the other prophets and messengers. If God destined me to enter Paradise, then we will not meet due to different degrees, as surely my degree in Paradise will be lower than yours. If God destined me to enter the Hellfire, then we will not meet.

Hearing this, the Prophet remained silent for a while to receive the following revelation shortly afterwards:

[And whoever obeys God and the Messenger, these are with those upon whom God has bestowed favors from among the Prophets and the truthful and the martyrs and the good, and a goodly company they are.] (An-Nisaa' 4:69)

Situations like the above should not pass unnoticed. The human touch of the Prophet and the way he approached his Companions and people in general did wonders. It ended up with people declaring that Muhammad is dearer to them than their wives, sons, daughters, parents, and selves.

Once the Prophet was once with his Companions. He then stretched his hand to `Umar ibn Al-Khattab. To that kind act, `Umar responded saying, "O Messenger of God, you are the most beloved to me after myself." The Prophet replied, "No, by Him in Whose Hand is my soul, you can't be a real believer until you love me more than yourself." To this, `Umar replied, " Now you are more beloved to me than myself." Then, the Prophet said, "Now, `Umar, your faith is complete" (Al-Bukhari).

These and many other countless events from the Prophet's biography demonstrate that Muhammad was a highly respectable, reputable, beloved, and kind character. Even before being divinely ordered by God to carry the divine message, he was called by his own tribesmen "As-Sadiq Al-Amin" (Arabic for "the truthful and the trustworthy").

People of Other Faiths

Muhammad's good manners were not confined to his close friends and Companions. His manners exceeded them to encompass different nationalities and creeds. He taught his Companions how to respect others regardless of their faith, race, color, or creed.

One day, he was sitting among his Companions. A funeral of a Jew from the people of Madinah was passing by, and upon seeing it, the Prophet stood up. His astonished Companions said, "O Prophet of God! He is a Jew." The Prophet taught them how to be respectful Muslims considerate to others' feelings by saying, "Isn't he the dead Jew a soul created by God?"

How far do we go in our hasty judgments on others? How many quick decisions do we make unknowingly and unwisely about our fellow humans? Don't we learn from the above example the respect Muhammad extended to a dead soul? He never derided or cursed a human being or even an animal. He was a caring and lovable character. Violence and harshness are never found in his dictionary.

Dealing With His Enemies

Many are the false, horrible stories one can hear and read about Prophet Muhammad being bloodthirsty and war-loving. Had those who study his character attempted to be objective in their studies, they would have realized that he was really a war-hating and merciful commander. He addressed his Companions on the night of the Battle of Badr saying, "Don't ever wish to meet the enemy, but if you are forced to , then be patient" (Al-Bukhari). "If you are forced to do that" means that confrontation was an option he did not prefer.

He was never offensive in his wars and military campaigns. His enemies ask for confrontation, and he enters wars for solely defending his beliefs and his community. He won the hearts of his enemies on the day he victoriously entered Makkah, without wasting a single soul.

One of the Companions, Sa`d ibn `Ubadah, once felt conceited on that day and raised his voice saying, "Today is the day of fierce war, a day in which inviolable rules will become violable, and a day to let Quraish taste humiliation." Upon hearing him, the victorious leader declared, "No, Sa`d! This day is the day of mercy. This is a day when honor cannot be transgressed. This is an honorable day for Quraish."

He never denied his enemies their dignity or honor. He never stripped them of their human characteristics.

He was someone who declared general amnesty before Amnesty International came to existence in today's world. He declared it before all and in broad daylight saying, "Go, you are free " These very people are those who drove the Prophet and all followers of Islam in Makkah out of their homeland (Makkah). They are the ones who relentlessly and fiercely oppressed him and his followers for more than 21 years.

Prophet Muhammad (peace be upon him) has been and will always be a human being from whom Muslims learn how to love and deal with one another, and form healthy relationships in today's global village. He left his personal impact on people as a human being before God entrusted him with His message.

Source - ReadingIslam.com

Muhammad - A man of charisma

By Prof. Shahul Hameed

Prophet Muhammad (peace be upon him) was always cheerful, genial, and pleasant-tempered. He was never rude or rough. He only spoke things that brought rewards from Allah (God) Almighty.

When he spoke, the listeners would listen to his words with attention. They did not feel any inclination to engage him in heated arguments. The Prophet would always show patience with a stranger's roughness of manners or harsh talk. He used to say:

"When you see a person seeking an object earnestly, assist him to get his need." (Al-Baihaqi)

And no wonder God Almighty said of the Prophet:

{And verily, you (O Muhammad) are on an exalted standard of character.] (Al-Qalam 68:4)

A person's face not only reflects the feelings of the heart, but also signals his or her attitude to the world around him or her. Indeed, you may even say that the total personality of a person is mirrored in the face.

And to speak about Prophet Muhammd, his smiling face was a source of solace and comfort to all those who came to meet him. Not just his words and actions, but the very expressions on his face shed rays of peace and tranquility into the hearts of those who were distressed by the pressures of life, or tormented by the afflictions of the soul.

Abdullah ibn Harith reported: "I have never seen anyone more in the habit of smiling than Allah's Messenger." (At-Tirmidhi)

The Prophet's smiles had spread such an aura of indescribable joy among his Companions to the extent that they forgot all their anxieties and worries in his presence and became totally fascinated with the Prophet himself.

The reason was that the Prophet was a perfect personality who always exuded a charisma of charm and geniality. His way was one of harmony and compassion. He was polite and considerate to everyone, and always kept a smiling face. Once, he told his Companions, "Smiling at your brother is a charity." (At-Tirmidhi)

There is an interesting incident reported by Saad ibn Abi Waqqas:

"Umar ibn Al-Khattab, one of the Prophet's Companions, asked his permission to see him. At the same time, there were some Quraishi women sitting with him asking him to give them more financial support, and they were raising their voices over the voice of the Prophet.

When Umar asked permission to enter, all of them hurried behind a screen. The Prophet admitted Umar, and he entered to find the Prophet smiling.

Umar said, "May Allah always keep you smiling, O Allah's Messenger! Let my father and mother be sacrificed for you!" (Note: This expression was used at the time to show one's love to another.)

The Prophet said, "I am astonished at these women who were with me. As soon as they heard your voice, they hastened behind a screen."

Umar said, "You have more right, that they should be afraid of you, O Allah's Messenger!"

And then he (Umar) turned towards them and said, "O enemies of your souls! You are afraid of me and not of Allah's Messenger?"

The women replied, "Yes, for you are sterner and harsher than Allah's Messenger."

Allah's Messenger said, "O Ibn Al-Khattab! By Him in Whose Hands my life is, whenever Satan sees you taking a route, he follows a route other than yours!" (Al-Bukhari)

Another Companion, Jarir ibn Abd-Allah, said: "Since the time I accepted Islam, the Prophet never once failed to notice me. Whenever he saw me, he would smile at me." (Al-Bukhari)

All those who knew the Prophet were fascinated and enchanted by the dignity and greatness of his character. His sweet and amiable expression made a profound impression on every stranger who met him.

No other person in history was privileged to have so many extraordinary qualities, and naturally, his Companions were ready to sacrifice their lives to protect him.

His hospitality and generosity were matchless; and he was the last man to get upset or angry. Indeed, he was so generous that he would never deny anything he was asked.

The forgiveness and general amnesty given by the Prophet to the Quraishis of Makkah, who had been insulting and persecuting him for over two decades, is well-known.

William Muir, the orientalist historian wrote, "The magnanimity with which Muhammad treated a people who had so long hated and rejected him is worthy of all admiration." (398)

Even the enemies of the Prophet acknowledged his justice and honesty: Long before he received prophethood, he was called Al-Ameen (that is, the truthful, the trustworthy). And so, his people always approached him for judgment and consultation.

He did not allow people to stand up out of respect upon seeing him, as they usually did before kings or leaders. Visiting the poor and the unfortunate and entertaining them were his constant habits. He had no hesitation in accepting the invitation of even a slave. He used to sit among the people like any one of them.

Simplicity, sincerity, and geniality were the keynotes of his character. The Prophet's wife, Aishah, said that he used to repair his shoes, sew his clothes, and share in domestic chores. He was most merciful, gentle, and amiable to all.

He was eager to serve anyone who served him. He was always in full control of his temper, and he never got angry unless it was absolutely necessary. If at all he was angry, it was for the sake of God and His religion, and not for his own sake.

The Prophet's magnanimity, broad mindedness, and tolerance embraced all people and entitled him to be a father to all of them.

He was careful to maintain an equal status with others and did not desire privileges. In an assembly he would seat himself at the least covetable position, next to the last person.

Whenever people came to meet him, he received them with honor and respect, so that each person addressed by the Prophet would think that there was no one more honored by the Prophet than him- or herself.

No questioner was disappointed when seeking advice from the Prophet.

To him the most favored one was the most pious one among the people. As for those persons who held high positions with their people, the Prophet was attentive to honor and respect them.

He never ignored his friends. Moreover, he used to visit them even during busy days, and inquired about their conditions.

The Prophet always adopted a moderate approach to all matters. He always chose the easier and the more pleasing way to solve problems.

While on his deathbed, the Prophet sent for the money in his house and distributed it among the poor. Immediately before he breathed his last, he had it publicly announced if anyone owed him anything, he may claim it; and if anyone was offended by him, he could have instant revenge.

Such was the Prophet of Islam, Muhammad.




Source - ReadingIslam.com