The triune brain is a model of the evolution of the vertebrate forebrain and behavior proposed by the American physician and neuroscientist Paul D. MacLean. MacLean originally formulated his model in the 1960s and propounded it at length in his 1990 book The Triune Brain in Evolution.^[1] The triune brain consists of the reptilian complex, the paleomammalian complex (limbic system), and the neomammalian complex (neocortex), viewed as structures sequentially added to the forebrain in the course of evolution.

The triune brain hypothesis became familiar to a broad popular audience through Carl Sagan‘sPulitzer prize winning 1977 book The Dragons of Eden. Though embraced by some psychiatrists and at least one leading affective neuroscience researcher,^[2] the model never won wide acceptance among comparative neurobiologists. Comparative evolutionary neuroanatomists currently regard its claims about brain evolution to be outdated.^[3][4]

The reptilian complex

The reptilian complex, also known as the R-complex or “reptilian brain” was the name MacLean gave to the basal ganglia, structures derived from the floor of the forebrain during development. The term derives from the fact that comparative neuroanatomists once believed that the forebrains of reptiles and birds were dominated by these structures. MacLean contended that the reptilian complex was responsible for species typical instinctual behaviors involved in aggression, dominance, territoriality, and ritual displays.

“After a caterpillar buries itself inside its cocoon, it waits to morph into a butterfly.  The caterpillar does not simply shrink a bit and sprout wings.  Instead, it disintegrates into a puddle of ooze within the cocoon.  If we were to open the cocoon halfway through the process, we would not find a half-caterpillar half-butterfly type creature, but a blob of goop.  The goop is made up of a bunch of individual cells that are all basically the same type of oozy cells.  After the caterpillar has turned into ooze, a new type of cells start appearing.  The original ooze cells are NOT changing into these new cells, but rather the new cells seem to come out of nowhere.  They just appear out of thin air so to speak.

These new cells are called imaginal cells and they are so completely different from the original ooze cells that they are thought to be a virus or some other form of enemy so the ooze cells begin attacking the imaginal cells.  However, even though the imaginal cells are being killed off for not fitting in, they still keep showing up, more and more of them.  Eventually, the imaginal cells begin to find each other and cluster together.  Like attracts like, and the clusters begin to join up with other clusters.  The original ooze cells still keep attacking them but the imaginal cells continue to multiply and cluster together.

Eventually, they become a large community and they switch gears from simply being a group of like-minded cells into the programming cells of the butterfly.  Some imaginal cells start changing into wing cells, some start changing into antenna cells, some start changing into digestive tract cells, and so on.  They are no longer imaginal cells but become butterfly anatomy cells.  As we all know, if left alone to do his thing, the butterfly eventually emerges as a completely new entity from the original caterpillar.  Do they hold the same memories, life lessons, and consciousness? ”

- In other words, the Caterpillar IMAGINES itself into a butterfly and thus becomes a butterfly….that’s amazing and spiritual relevant, don’t you think? Is this nature’s example of conscious transformation?

If your child hasn’t received the whooping cough vaccine, he or she is now banned from attending class at many California schools. Despite legitimate religious or personal health reasons for rejecting the whooping cough vaccine, your child simply cannot attend class. Due to a law that requires all students entering grades seven through 12 be vaccinated, the San Francisco school district has begun sending home children who do not have proof of receiving the whooping cough vaccination.

Proof of vaccine ineffectiveness

Why are schools afraid of unvaccinated children spreading the disease to vaccinated childrenif the whooping cough vaccine is truly effective? How could an unvaccinated child spread the disease to someone who has already received the whooping cough vaccine?

Interestingly enough, scientists have found that vaccinating against the whooping cough is actually an ineffective waste of money. In fact, widespread vaccination of adults against whooping cough (pertussis)would do almost nothing to reduce infection rates among unvaccinated children according to a study conducted by researchers from the University of Michigan and published in the journal Science.

The IB Times reports:

The law, which requires that all students entering grades seven through 12 be vaccinated, took effect for the 2011-2012 school year. The state legislature passed a 30-day extension over the summer to give students more time to comply, but thousands of students still have not gotten the vaccine — and, depending on the school district they’re in, some of them can’t attend class until they do.

Starting on Thursday, the San Francisco school district sent home students who came to school without proof of vaccination or a signed “parental personal belief exemption,” in which parents can certify that they have chosen not to vaccinate their child because of personal opposition to vaccinations.

Please begin your research into the dangers of vaccines with 100 Compiled Studies on Vaccine Dangers showing them to be ineffective, or outright dangerous, and use this to educate those around you.  Please also visit Natural Society for additional info. about vaccine dangers, alternative medicine, and natural health.

Post taken from:

http://www.infowars.com/california-bans-unvaccinated-children-from-class/

By Jennifer Viegas
Fri Mar 18, 2011 07:00 AM ET

God had a wife, Asherah, whom the Book of Kings suggests was worshiped alongside Yahweh in his temple in Israel, according to an Oxford scholar.

In 1967, Raphael Patai was the first historian to mention that the ancient Israelites worshiped both Yahweh and Asherah. The theory has gained new prominence due to the research of Francesca Stavrakopoulou, who began her work at Oxford and is now a senior lecturer in the department of Theology and Religion at the University of Exeter.

Information presented in Stavrakopoulou’s books, lectures and journal papers has become the basis of a three-part documentary series, now airing in Europe, where she discusses the Yahweh-Asherah connection.

“You might know him as Yahweh, Allah or God. But on this fact, Jews, Muslims and Christians, the people of the great Abrahamic religions, are agreed: There is only one of Him,” writes Stavrakopoulou in a statement released to the British media. “He is a solitary figure, a single, universal creator, not one God among many … or so we like to believe.”

“After years of research specializing in the history and religion of Israel, however, I have come to a colorful and what could seem, to some, uncomfortable conclusion that God had a wife,” she added.

Stavrakopoulou bases her theory on ancient texts, amulets and figurines unearthed primarily in the ancient Canaanite coastal city called Ugarit, now modern-day Syria. All of these artifacts reveal that Asherah was a powerful fertility goddess.

Asherah’s connection to Yahweh, according to Stavrakopoulou, is spelled out in both the Bible and an 8th century B.C. inscription on pottery found in the Sinai desert at a site called Kuntillet Ajrud.

“The inscription is a petition for a blessing,” she shares. “Crucially, the inscription asks for a blessing from ‘Yahweh and his Asherah.’ Here was evidence that presented Yahweh and Asherah as a divine pair. And now a handful of similar inscriptions have since been found, all of which help to strengthen the case that the God of the Bible once had a wife.”

Also significant, Stavrakopoulou believes, “is the Bible’s admission that the goddess Asherah was worshiped in Yahweh’s Temple in Jerusalem. In the Book of Kings, we’re told that a statue of Asherah was housed in the temple and that female temple personnel wove ritual textiles for her.”

J. Edward Wright, president of both The Arizona Center for Judaic Studies and The Albright Institute for Archaeological Research, told Discovery News that he agrees several Hebrew inscriptions mention “Yahweh and his Asherah.”

“Asherah was not entirely edited out of the Bible by its male editors,” he added. “Traces of her remain, and based on those traces, archaeological evidence and references to her in texts from nations bordering Israel and Judah, we can reconstruct her role in the religions of the Southern Levant.”

BLOG: Atheists Best Informed About Religion

Asherah — known across the ancient Near East by various other names, such as Astarte and Istar — was “an important deity, one who was both mighty and nurturing,” Wright continued.

“Many English translations prefer to translate ‘Asherah’ as ‘Sacred Tree,’” Wright said. “This seems to be in part driven by a modern desire, clearly inspired by the Biblical narratives, to hide Asherah behind a veil once again.”

“Mentions of the goddess Asherah in the Hebrew Bible (Old Testament) are rare and have been heavily edited by the ancient authors who gathered the texts together,” Aaron Brody, director of the Bade Museum and an associate professor of Bible and archaeology at the Pacific School of Religion, said.

Asherah as a tree symbol was even said to have been “chopped down and burned outside the Temple in acts of certain rulers who were trying to ‘purify’ the cult, and focus on the worship of a single male god, Yahweh,” he added.

The ancient Israelites were polytheists, Brody told Discovery News, “with only a small minority worshiping Yahweh alone before the historic events of 586 B.C.” In that year, an elite community within Judea was exiled to Babylon and the Temple in Jerusalem was destroyed. This, Brody said, led to “a more universal vision of strict monotheism: one god not only for Judah, but for all of the nations.”

-From Discovery News

http://abcnews.go.com/US/wireStory?id=14306999

Photo: Associated Press

Elaine Riddick’s small frame heaves, her rapid, shallow breaths whistling in her throat as she forces the words out between her sobs.

“So what am I worth?” she asks the five people seated at the long table before her. “The kids that I did not have, COULD not have. What are THEY worth?”

“Priceless,” Tony Riddick whispers as he gently rubs his mother’s back.

Elaine Riddick has been asking these same questions, in one forum or another, for the past 40 years. This most recent appearance in late June was before the Governor’s Task Force to Determine the Method of Compensation for Victims of North Carolina’s Eugenics Board.

As far as Riddick is concerned, she tells the panel, she was raped twice. Once by the man who fathered her son, and again by the Eugenics Board of the State of North Carolina, which deemed her, at age 14, unfit to procreate.

“I am NOT feebleminded,” she shouts, turning to face the packed hearing room. “I’ve never BEEN feebleminded.”

“No,” says her son, standing beside her behind the podium.

Tears streaming down her face, she says, “They cut me open like I was a HOG.”

Between 1929 and 1974, North Carolina sterilized more than 7,600 individuals in the name of “improving” the state’s human stock. By the time the program was halted, the majority of those neutered were young, black, poor women — like Riddick.

In many ways, Riddick’s has become the face of the movement to compensate victims of what most now acknowledge as a dark, misguided era in the state’s — and nation’s — past. From her decision to sue the state in federal court nearly four decades ago to this most recent baring of her soul, she has refused to simply fade from view.

Instead, the 57-year-old Riddick has become an inspiration to other survivors of the state’s eugenics program.

One of them is Australia Clay, whose mother was sterilized, and who, following Riddick to the podium, tells her how lucky she was to have had Tony — no matter how violently he was conceived.

“You’re blessed,” Clay says through her own tears. “‘Cause he can help fight for you now. I see God’s hand in your life.”

Riddick says she never felt otherwise.

The sun is almost infernal as Tony Riddick steps from the air-conditioned sanctuary of his SUV and strolls down Louise Street in this rural crossroads where the Perquimans River empties into Albermarle Sound. Pearls of sweat dot his shaved head as he makes his way to a simple gray frame house beside a drainage ditch that separates the road from the farm field beyond.

When he was growing up, folks used to call this section of town “Little Korea” — because the violence and poverty reminded them of a Third World country.

“This right here is a good example of what God is capable of doing,” Riddick says, gesturing around him. “My mother’s life and my life, by ANY measure, would have been, should have been, COULD have been totally written off.”

The house belonged to Elaine Riddick’s maternal grandmother, Maggie Woodard — “Miss Peaches,” as she was known. The two-bedroom home was a refuge of sorts, with 10, sometimes 15 people spilling onto pallets on the floors.

By age 13, Delores Elaine Riddick had taken refuge here.

World War II had left her father, Army veteran Thomas Cleveland Riddick, an abusive, alcoholic, “shell-shocked” husk of a man; her mother, Pearline Warren Riddick, was in the women’s prison for assaulting her husband. The Director of Public Welfare for Perquimans County had taken custody of Elaine, and Woodard was receiving government surplus food for the girl.

Riddick, third-oldest in a family of seven girls and one boy, was forced to wear the same clothes several days in a row. Picked on by bullies, she often skipped school.

With so many children in the house, there was little supervision. Riddick would go to friends’ houses for dances and stay out late.

One Sunday evening, around dusk, she was walking home alone from a party when a man jumped out of the bushes of an abandoned house about two blocks from her grandmother’s. Clapping one hand over her mouth and twisting her arm behind her back with the other, he led her to a nearby car and raped her.

She knew the man from the neighborhood. He was 10 years her senior.

He said if she ever told anyone, he would kill her.

At 13, Riddick knew nothing about where babies came from, let alone morning sickness. So when she became ill while picking cucumbers one day, she told her grandmother she thought someone had poisoned her.

When Woodard finally learned that her granddaughter was pregnant, Riddick was afraid to tell the truth. She said the father was an older boy from nearby Edenton whom she’d met at a party.

It was a lie that would come back to haunt her.

After Thomas Anthony Riddick was delivered on March 5, 1968, Riddick remembers awaking to find her abdomen swathed in bandages.

What she didn’t know was that a month and a half earlier, five men sitting around a table across the state in the capital had decided that Riddick’s first child should be her last.

The word “eugenics” comes from the Greek for “well-born.”

By the early 20th century, most U.S. states had eugenics programs, and more than 30 enacted laws mandating surgical sterilization for certain individuals. It is estimated that as many as 100,000 people were sterilized in the country before the practice was discredited.

On Jan. 23, 1968, members of the North Carolina Eugenics Board met in Room 539 of the state Education Building in Raleigh to consider the latest petitions for “operation of sterilization or asexualization.” Among them was Case No. 8: “Delores Elaine Riddick — (N) — Perquimans County.” The “N” stood for Negro.

Board members were given a summary of each case. The board secretary would place the complete files in the center of the table, should a member need additional information before making a decision.

Riddick’s file contained an evaluation from Dr. Helton McAndrew, a clinical psychologist.

A year earlier, social services had ordered Riddick examined for possible placement in an orphanage. On April 5, 1967, not long before the rape, McAndrew met with the troubled 13-year-old.

Despite reports that she was irritable and anti-social, McAndrew found Riddick “well behaved, pleasant and cooperative.”

“She attends school regularly and is neat in spite of not having sufficient clothes,” he wrote. “She is generally hungry which is probably an important factor in her being easily irritated and having difficulty getting along with others.”

She told McAndrew she wanted to go to college and become a nurse.

Although she was in the “slow section of the seventh grade,” testing revealed that Riddick had an IQ of 75 and a mental age of 9 years and 10 months. McAndrew felt that her “tremendous feelings of insecurity stemming from the disturbed home conditions” were causing her irritability and “also repressed her level of intellectual functioning.”

“Delores Riddick’s chief problem is her poor home,” he concluded. “We expect this girl to perform more adequately in an improved environment.

Social worker Marion Payne took a dimmer view of things.

While McAndrew found that Riddick was “comparatively at ease in school” and was “doing above average work,” Payne reported that the child did “poor school work” and “does not get along well with others.”

Payne noted that the family had been receiving public assistance for much of the previous decade, and that both parents were alcoholics. A doctor had assessed Riddick as “feebleminded.”

“Because of Elaine’s inability to control herself, and her promiscuity — there are community reports of her ‘running around’ and out late at night unchaperoned, the physician has advised sterilization,” the final recommendation read. “This will at least prevent additional children from being born to this girl who cannot care for herself, and can never function in any way as a parent.”

Three weeks before the board meeting, Thomas Riddick had signed a form consenting to the procedure — even though he no longer had custody of his daughter. Payne also reported that the situation had been explained to Woodard, and that she agreed that it would be best if her granddaughter had no more children.

And so, after delivering Riddick’s son, Dr. William Bindeman clipped, resected and cauterized her fallopian tubes.

Riddick developed an infection and had to remain in the hospital for another week. Her grandmother took Tony home.

Riddick tried to be a mother to her son. She breast-fed and bathed him. But her grandmother, concerned about bad influences in the local environment, decided to send her to live with an aunt on Long Island, N.Y.

At 18, Riddick married a man she met in New York. When the new couple’s efforts to conceive failed, Riddick went to a specialist. It was then, she says, that she learned what the surgeon had done four years earlier.

Riddick says her inability to bear children drove a wedge between her and her husband, contributing to their eventual breakup. She says she went into a kind of “hibernation.” When friends became pregnant, she withdrew from them, unable to bear the pain of witnessing their joy.

“I became a hermit,” she says. “I locked myself away. I hid within my own self.”

During a visit home shortly after learning the truth about her operation, Riddick was watching her grandmother rake the front yard and suddenly dissolved into tears. She told her what the doctor had said, and asked why she had allowed her to be sterilized.

All Woodard could remember was the social worker handing her a piece of paper and saying that if she refused to sign her mark, the family’s food supplements would be cut off.

“Lord knows I didn’t know what I was doing,” she told Riddick. “Lord knows I would never do that to you.”

Her granddaughter believed her.

After about a year of this self-imposed exile, a sister suggested Riddick do something about it. She went to see the American Civil Liberties Union.

In 1973, the group’s Women’s Rights Project — then under the direction of future Supreme Court Justice Ruth Bader Ginsburg — had filed a federal suit against the state of North Carolina on behalf of another victim of the sterilization program. They were looking for more plaintiffs to join a class action.

Delores Elaine Riddick stepped forward.

On Jan. 18, 1974, ACLU attorneys filed suit in U.S. District Court against the members of the state Eugenics Commission, as it was by then known, local social workers and the hospital where the operation was performed. She was seeking $1 million.

It would be nine years before the suit would go to trial. As the case wound its way through the process, and defendants were dismissed and added, Riddick tried repair the physical and emotional damage she had suffered.

During summer vacations, Tony would come to New York for visits. She divorced and rediscovered love.

In October 1981, Riddick underwent an operation to reverse her sterilization. Doctors could only repair one side, and even then placed her chances of becoming pregnant at only 50 to 60 percent.

Riddick, who dropped out in the eighth grade, obtained her high school equivalency diploma. In June 1982, she graduated from the New York City Technical College with an associate’s degree in applied science.

“She was put in a prison of pain that stayed with her for a long, long time after that operation.”

The trial ended on Jan. 19, 1983. It took the jury just 45 minutes to render its verdict.

When asked whether Riddick had been “unlawfully or wrongfully deprived of her right to bear children as a proximate result of the actions of any of the defendants,” the jury replied, No.

Flaxman took the case all the way to the U.S. Supreme Court. On Oct. 1, 1984, the high court declined to hear it.

Following the trial, Riddick moved to suburban Atlanta to live with one of her younger sisters. Her son eventually joined her there.

Riddick had largely abandoned any hope of justice until about a decade ago, when a team of Winston-Salem Journal reporters investigating the state’s eugenics program learned of the lawsuit and tracked her down. When the series “Against Their Will” ran in late 2002, Riddick’s story was a centerpiece.

One of the series’ most striking findings was the eugenics program’s apparent racial and sexual bias. During the program’s first decade, 79 percent of those sterilized were white; by the time Riddick’s case was decided, 64 percent of the operations were being performed on black females.

Following the revelations, then-Gov. Mike Easley issued an apology to eugenics victims and their families. Victims were also offered some special health and education benefits.

But the Riddicks and others pushed for monetary reparations.

In October of 2008, Riddick traveled from Georgia to testify before a legislative committee, which recommended giving each victim $20,000. Running for governor, Beverly Perdue vowed to get the funding but, once elected, she ran headlong into a $4.6 billion budget gap.

In 2009, Perdue and the Senate set aside $250,000 for the newly created Justice for Sterilization Victims Foundation to identify victims and develop a plan to compensate them. Later that year, Riddick returned to Raleigh for the dedication of a historical marker a block from where the decision was made to sterilize her.

This March, Perdue created the five-member task force. When it held a public hearing on June 22, Riddick and her son were there.

Trembling with hurt and rage, Riddick posed her existential question to the panel, then answered it herself.

“It doesn’t matter what you think I’m worth,” she said, almost spitting the words. “It’s what I think I’m worth. There’s nothing that the state of North Carolina can do to justify what they did to me — what they did to these other victims.”

Taking his mother’s place at the microphone, Tony Riddick said the eugenics program was nothing short of attempted “genocide.”

“What did God ask her to do? He asked her to be prolific. Be fruitful. Go out and multiply, replenish the Earth,” he said. “And you took all of that, not just away from her, but from other men and women here in this audience. And you did it for reasons you knew were wrong.”

About halfway through the hearing, Gov. Perdue slipped silently into the chamber and took a seat at the back. After listening quietly for several minutes, her brow furrowed, she stood and addressed the victims.

“It’s hard for me to accept or to understand or to even try to figure out why these kinds of atrocious acts could have been committed in this country … and I just came here as a woman, as a mama, and as a grandmama and as governor of this state, quite frankly, to tell you it was wrong,” she said. “It makes you wonder who we were as a people during those years. The state of North Carolina is a partner with you in trying to bring awareness and to redress, in some way, however we may, these awful ills …”

Elaine Riddick listened intently to the governor, then the tears began flowing again. She turned away and bowed her head as her son draped his arm around her shoulders.

The task force delivered a preliminary report to Perdue Aug. 1. Among its recommendations were unspecified “lump sum financial damages” and mental health services for living victims.

“For many citizens, it may be hard to justify spending millions when the state is cutting back on other essential services,” the panel wrote in a letter to the governor. “But the fact is, there never will be a good time to redress these wrongs and the victims have already waited too long.”

A final report is due Feb. 1, 2012.

Despite her reconstructive surgery, Riddick was never able to have more children.

But she knows she has much for which to be thankful.

She has love in her life. Riddick met Paul Adams about 15 years ago, when he offered to share his table with her at a crowded Waffle House. She and the Air Force retiree — who is bedridden with multiple sclerosis — were married this past January.

She has a 6-year-old grandson, Tony Riddick Jr.

And she has Tony.

“I thank God today that I have my son,” she says. “To me, he’s a blessing and he’s a gift.”

After graduating from college, Tony Riddick moved to Hertford, just a few miles from where he and his mother grew up. He is president of his own computer-electronics company.

He has filled his spacious, two-story home with objects of deep personal meaning to him. Against one wall of his living room stands a wooden bust of Miss Peaches; across the way lie a pair of heavy iron slave shackles.

Tony Riddick says he was about 13 when he learned that his mother had been sterilized. He didn’t learn about the circumstances of his conception until much later.

About that, he says, “You know, the spirit of God is the authority. And he deemed it necessary that I come in the way that I came in. And because I’m such a firm believer in that, I wouldn’t question how he decided to bring me in, because I know it has a greater purpose.”

His mother, too, speaks of a divine hand in events.

“I’m on a mission,” she says. “And God is using me as an instrument to do his will.”

She feels compelled to speak out, not just for herself, but for those who might be too afraid or ashamed to speak for themselves. The task force estimates that as many as 2,000 victims of the state’s eugenics program may still be alive.

The apology was a step in the right direction. But Riddick thinks someone should be made to pay for what was done to her and the others.

Her son is confident they will prevail — “because she’ll never stop fighting.”

******

Allen G. Breed is a Raleigh, N.C-based national writer for The Associated Press. He can be reached at features(at)ap.org.

Discovery News:http://news.discovery.com/space/earth-moon-life-tilt-110808.html

Getty Images

Scientists have long believed that without the moon’s stabilizing gravitational influence, variations in Earth’s tilt would have caused climate change too dynamic for complex life to evolve. Not so, concludes a new study that has implications for understanding conditions for life elsewhere in the solar system.

The study sprang from the ongoing Kepler Telescope mission to find Earth-like planets circling in habitable zones around other stars in the Milky Way.

“We were wondering ‘Do we really have to find a moon or not?’ around potentially habitable worlds, planetary scientist Jason Barnes, with the University of Idaho, told Discovery News.

NEWS: Earth May Have Had Two Moons

Previous studies showed that without the steadying gravitational influence of a large moon, Earth’s tilt would shift by as much as about 85 degrees every 100,000 years or so, alternatively freezing and baking the planet’s poles. Scientists believe a stable climate spanning about 500,000 years was necessary for complex life to blossom on Earth.

A new computational analysis, however, shows that a moonless Earth would still have swings in its tilt but the influence of Jupiter and other factors would limit the variations to about 10 degrees in either direction.

Earth’s rotational tilt varies between 0.5 and 1 degree about every 100,000 years.

“Plus- or minus-10 would certainly be noticeable and may be a problem, but I don’t think it would prevent life from coming about,” Barnes said.

NEWS: Subterranean Living May Await Moon and Mars Colonists

“It’s a very intriguing result. It’s provocative,” Richard Vondrak, lead scientist with NASA’s ongoing Lunar Reconnaissance Orbiter mission, told Discovery News.

“On the moon we can find important evidence and clues of what happened to not only to the moon, but also to the Earth-moon system over the last 4.5 billion years,” said Vondrak, a planetary scientist with NASA’s Goddard Space Flight Center in Greenbelt, Md.

The study also showed that if Earth revolved around the sun in the opposite direction, called a retrograde orbit, it wouldn’t need a moon at all to have a climate about as stable as it has today. Likewise, a Jupiter about half the distance to Earth as its present location would have had a similar steading hand, Barnes added.

The findings are causing extrasolar planet hunters to revise their thinking on what constitutes a habitable planet.

“We think that at least 80 or 90 percent of planets out there statistically won’t even require a moon” to have a stable climate, Barnes said.

Location is key. In our own solar system, Mars shows evidence of extreme climate change, the result, scientists believe, of a rotational tilt that flips between zero and 60 degrees over time. A big moon likely could have helped stabilize Mars’ orbit, but the planet has just two small moons, most likely captured asteroids, that don’t have much gravitational muscle.

Other factors impacting a planet’s climate and suitability for life include its star’s age, composition and the size and location of sibling planets in the system.

“It’s a very complex problem for sure and we’re not anywhere near solving it, but we’re making positive steps as we slowly evaluate each of these conditions and discover what constraints they really place on whether life can exist there,” Barnes said.

The research appears in this month’s Astrobiology magazine and is pending publication in the journal Icarus.