​In the case of your intelligence, "I got it from my mama" couldn't be more accurate. New research featured in Psychology Spot says people are born with conditioned genes that work differently depending on if they're from your mother or father - and when it comes to your intelligence, those genes are from mother dearest.
Even though people used to believe your smarts were from your father and mother, that's not the case. You see, intelligence genes are located on chromosome X and since women carry two, that means children are twice as likely to get their intelligence from mom. 
And even if your father passes off a few of his intelligence genes to you, chances are they won't have an impact on your brain since they only work if they come from your mother. "If that same gene is inherited from the father, it is deactivated," reports the study inPsychology Spot. "Obviously, other genes work the opposite, are activated only if they come from the father." 
Want even more proof? The Medical Research Council Social and Public Health Sciences Unit in the United States did a study on mothers back in 1994 and interviewed 12,686 young people between the ages of 14 and 22. Their questions focused on the children's IQ, race, education and socio-economic status. The best predictor of intelligence? The IQ of their mother.

Maria da Penha: The woman who changed Brazil's domestic violence laws

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In September 2006, Brazil introduced ground-breaking legislation on domestic violence. It was called the Maria da Penha Law after a women's rights activist who was left paraplegic by her violent husband. Here, she tells her remarkable story.
When Maria da Penha was almost killed by her husband, there wasn't a single police station she could go to in Brazil specialising in violence against women.
"At that time we weren't even aware of this expression - domestic violence," she says. "You just had a bad husband."
It's over 40 years since Maria da Penha first encountered the man who would change her life so dramatically.
She was studying to become a bio-pharmacist in Sao Paulo when she met Marcos Antonio Heredia Viveros, a schoolteacher originally from Colombia, through mutual friends. He was likeable and helpful, and they quickly fell in love. In 1976 they were married.
After Maria finished her studies, the couple moved back to her home city of Fortaleza, on Brazil's north eastern coast, and they began a family. But the man she had fallen in love with soon began to change.
"When his Brazilian citizenship was granted, he showed his true colours," Maria recalls. "I had no idea of how to make him go back to what he was like before.
a"I didn't know if he would wake up in a good mood or a bad mood. He became violent, hitting the children for no reason. That started to make me feel unsafe in my marriage."
Maria says there was no single trigger for the change in his behaviour. And anything, however big or small, would set him off.
"At the time my daughters were aged seven, five and almost two. My little one still wasn't walking. One day she was sitting on the floor and she wet herself.
"Then she got up and with her little wet hands, she tried to support herself using the wall. She got the wall wet. So he hit her and shouted at her. He really slapped her hard."
Maria's middle daughter used to suck her thumb, and he tied her hands to stop her doing it.
"I wasn't here, I was told about this later," says Maria. "When she managed to untie it, he hit her hard and put her in the shower under cold water."
As the violence continued, Maria felt trapped, isolated and alone.
"The only people who knew that I was suffering abuse were me and the girls who lived with us," she says. "I spared my family because if they knew they would have told me to get a divorce."
Find out more

• Maria da Penha spoke to the BBC World Service Witness programme
• Listen via the BBC iPlayer or download the podcast

But things came to a head one terrible night in May 1983. Maria was at home with her husband and children.
"I was sleeping when I heard a big bang in the room. I tried to move and couldn't. Immediately I thought: 'Marco has killed me.'
"Our neighbours, who were doctors, came and found me in a terrible state, lying on the bed, on top of the wound. There was a hole in my back and I was losing a lot of blood onto the mattress. The mattress was soaked."
Maria had been shot by her husband, the bullet lodging in her spine.
But her husband told police that he'd been woken up by a noise, and had got up and found four strangers in the house. After a struggle, he said they'd tied him up and then they had shot Maria.
The police appeared to believe him, and since she was immediately rushed to hospital, Maria's version of events was not heard until later. No one was arrested.
As in many parts of the world, domestic abuse was - and still is - common in Brazil. But victims seldom went to the police.
In the early 1980s there were no specialised police units dealing with such cases, and it wasn't until 1988 that thanks to pressure from women's organisations, Brazil's constitution was amended to include guarantees of equality for women victims before the law.
But even then, the police lacked specific powers to act. For instance, there were no banning or restraining orders.
Image copyrightFOTOS GOVBA/FLICKRAnd well into the 1990s, the courts in Brazil still accepted that a man who murdered his unfaithful wife could claim a defence of "dishonour".
After four months in hospital, Maria, now paralysed from the waist down, returned to the family home.
The police investigation into the shooting was still inconclusive. And even Maria herself was beginning to doubt whether it really could have been her husband. She had no evidence to back up her suspicions.
But once she was home, the abuse continued.
"The day I came back, he told me as we were still driving home that I wasn't to have any visitors - no neighbour, no friends, no family - without his consent," Maria says.
"I was kept under a sort of house arrest. My family would call and I'd make up excuses - I'd tell them: 'I'm too tired' - so that they wouldn't come to see me. So as to obey his orders."
Eventually, in spite of everything she'd been through and in spite of her husband's attempts to keep her isolated from the outside world, Maria began to look for a way out.
Without her husband's knowledge, she tried to get a court order giving her custody of the children so that she could flee the house.
Before she could do so, Viveros made one more attempt to kill her - this time trying to electrocute her by tampering with the electric shower when she was bathing.
Miraculously, she survived - and then left for good.

"I spent 19 years and six months fighting for him to be jailed, and during that time he was put on trial and found guilty twice, and twice he walked out of the court free because of the appeals," she says.
In 2002, Viveros was eventually sentenced to eight years in prison - though he was released after just a year. Meanwhile, Maria was campaigning for changes in the law.
And she even took her case to the Organisation of American States.
Eventually in August 2006, Brazil's left-wing president Luiz Inacio Lula da Silva signed the Lei Maria da Penha, the Maria da Penha law. It came into effect on 22 September 2006.
For the first time in Brazil, the law recognised different forms of abuse against women.

It increased the punishment for offenders, established special domestic violence courts and required the authorities to open 24-hour shelters for abused women. It was heralded as landmark legislation on domestic abuse by the United Nations.
Maria da Penha, who's now 71, still campaigns tirelessly on women's rights and travels the country speaking about her own harrowing experience. She believes the law bears her name was a great victory - but it was just a first step, she says.
"So many women think that violence is only physical, they are not aware of other kinds of violence," she says. "They don't understand psychological, moral, sexual violence. The law lists all those kinds of abuses.

"Nowadays women are coming forward but the violence continues. They are coming forward to press charges, but it's only in the cities or the state capitals where there are shelters and specialised police units and all the facilities."
There's a long way to go to change attitudes, she says.
"Listen, the law is now very well-known across Brazil, 98% of the country has heard of it. Many women tell me that they would be dead without the law.
"But there is still a long way to go. No woman deserves to be suffering like that."

Theresa May Heads To G20 In China
Theresa May’s officials have been warned to avoid “honey traps” amid fears that the Prime Minister's team will be targeted by Chinese spies offering sex during the G20 summit. 

British government aides have fallen victim to spying on previous official trips to China, with one Downing Street official reported to have had his mobile phone and secret documents stolen after he was seduced.
Government security chiefs are anxious to avoid a repeat of the incident, which took place during a visit by Gordon Brown in 2008, and have provided detailed guidance to Mrs May’s team.


The Prime Minister’s officials have been warned to take steps to protect themselves during the G20 summit, which begins on Sunday .


Officials travelling with Mrs May have been issued with temporary mobile phones and email addresses in an attempt to evade Chinese state hackers.
Security advisers are also warning staff not to keep gifts they receive and to be particularly wary of electronic devices, such as free computer memory sticks, mobile phone SIM cards or chargers which they are offered by their Chinese hosts.


© PA Prime Minister Theresa May and Chancellor of the Exchequer Philip Hammond at Heathrow Airport before she boards a plane for the G20 Summit in Hangzhou in China which begins on Sunday.One Whitehall source said security chiefs had warned them that hotel rooms used during the summit were likely to be bugged. “We have been told that if you feel uncomfortable about people seeing you naked, you should get changed under your bedclothes,” the source said.


British security agencies regard China as one of the most aggressive nations when it comes to launching cyber-attacks against western governments and businesses, as well as posing a major espionage threat to the UK.


Chinese technological expertise has prompted security concerns at the highest levels of government and British intelligence. 


There are fears that Chinese intelligence agents will use their capability to intercept emails and phone calls and to install spy software on computers during the summit. 
However, one of the gravest threats posed by foreign spies is also one of the oldest: the honey trap.


During Mr Brown’s visit to China in 2008, one of the No 10 officials accompanying the then Prime Minister reportedly fell prey to a “beautiful” female Chinese spy. She went back to his hotel room, drugged him, stole his mobile phone and documents from his briefcase.


The incident was described by Mr Brown’s former spin doctor, Damien McBride, in his 2013 memoir, Power Trip.


The No 10 team was “accosted on one side by a beautiful posse of Chinese girls and on the other side by an equivalent group of Russian blondes”, Mr McBride said.
He wrote: "Even before our resident security expert could warn us that their interest was not to be taken at face value, we looked up and saw one of our number disappearing up the stairs to the exit with one of the girls, beaming back at us."
He woke up the following morning "minus his Blackberry and half the contents of his briefcase". 


The official also had a "‘very bad headache, owning to the Mickey Finn nightcap his overnight companion had administered to him in his hotel room".


The G20 summit in Hangzhou comes at a time of heightened tension between Britain and China. Within weeks of entering Downing Street in July, Mrs May put on hold a final decision on whether to approve a Chinese-backed new nuclear power station at Hinkley Point in Somerset.


Her aides made it clear that she was concerned about the potential risks to British national security of allowing China to take such a major role in running a critical nuclear energy plant.


Mrs May’s chief of staff, Nick Timothy, warned before taking up his No 10 role that the Hinkley project could allow China to shut down energy production “at will”.
He said that MI5 believed Chinese intelligence services were working “against British interests at home and abroad”.


Shortly after Mrs May’s decision to delay the Hinkley plan, the Chinese ambassador in London warned that blocking the £18 billion project would put Britain’s future relationship with China in doubt.


Mrs May is due to have her first face-to-face meeting with the Xi Jinping, the Chinese president,  at the end of the G20 summit on Monday.