Scientist Says Our Oldest Ancestor May Have Been Only ‘Half Alive’

Home, sweet home in the heat and chemical chaos of a hydrothermal vent. Image credit: NOAA Vents Program via Wikimedia Commons // Public Domain

Here are some things we think we know about the first organism to ever appear on Earth: Its name was LUCA. It lived on the hot sea floor about 4 billion years ago. And although it eventually gave rise to every person, plant, and virus alive today, scientists now say LUCA itself might only have lived a sort of half-life. They published these controversial findings in Nature Microbiology.

LUCA (our Last Universal Common Ancestor) may have been cruder than a single-celled bacterium, but that doesn’t make it uninteresting. Quite the opposite, in fact: This older-than-old organism could teach us volumes about the appearance of life on Earth as we know it.

The tricky part of studying an ancient, formless organism is that it could leave no footprints, feathers, or bones behind. Fortunately, LUCA left something better: its genes, moving forward through time.

Researchers at Heinrich Heine University (HHU) in Dusseldorf, Germany set out to find LUCA’s genes in its single-celled descendants, bacteria and archaea. They combed the genomes of 1847 bacterial and 134 archaeal species, looking for shared genetic material. Any proteins that appeared in at least two groups of bacteria and two groups of archaea would likely signify a common parent.

The team found 355 overlapping protein clusters out of the 286,514 they examined. The shared proteins suggested that LUCA was even more primitive than scientists had previously imagined. The genetic lines drew a picture of an organism getting by in the dark of a boiling, oxygen-less hydrothermal vent, feeding on hydrogen gas and metals.

The life LUCA led was so very different from our own that study co-author William F. Martin told The New York Times it could be considered just “half alive.”

If you consider LUCA a biological bridge between a lifeless planet and the life forms that came after it, this framework makes sense. But that theory has its detractors.

Biochemist Steven Benner, a distinguished fellow at the Foundation for Applied Molecular Evolution, told the Times that if LUCA could synthesize proteins—and the genetic analysis suggests it could have—the organism could likely synthesize other, simpler things as well, even if the HHU team didn’t find them. “It’s like saying you can build a 747 but can’t refine iron,” he said.

Chemist John Sutherland of the University of Cambridge had his own objections. He says that LUCA’s dependence on its environment was not as extreme as Martin makes it out to be. “It’s like saying I’m half alive because I depend on my local supermarket.”

Sutherland and Benner don’t disagree with the HHU researchers’ conclusion that LUCA was, well, our LUCA, and they’re fine placing it on a hydrothermal vent. But they don’t think LUCA was the first life form, and they say a lot more research is needed before we can really pin down just what that ancient little weirdo was up to. 

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Courtesy of October Films
This Scientist's Idea of the 'Perfect' Human Body Is Kind of Terrifying
Courtesy of October Films
Courtesy of October Films

The perfect human body has the legs of an ostrich, the heart of a dog, and the eyes of an octopus, according to anatomist Alice Roberts. And it’s utterly terrifying.

With the help of anatomical artist Scott Eaton and special effects designer Sangeet Prabhaker, Roberts created a life-size replica of herself that fixes many design flaws inherent to the human body, Motherboard reports. Roberts unveiled the sculpture on April 23 at the Science Museum in London. On June 13, the BBC released a documentary about the project.

Among the flaws Roberts’s sculpture corrects are humans’ inferior ears, spine, and lungs. Roberts borrowed anatomy from reptiles, birds, and other mammals to create a Frankenstein-esque creature straight from the island of Dr. Moreau.

The sculpture of Alice 2.0, left, with Alice Roberts, right
Courtesy of October Films

The sculpture has legs like an ostrich because, as Roberts says on her website, the human knee is complex and prone to failure. Like humans, ostriches are bipedal, but they are far better runners. Bird-like lungs that keep air flowing in one direction, not two, make running and other aerobic activities easier for the perfect human to manage. And a chimpanzee’s sturdier spine and a dog’s heart (which has more connected arteries, leading to lower heart attack risk) make Roberts’s alternate self more resistant to injury and disease.

Robert’s ideal human body also has skin like a frog that can change shades based on the environment, and large, bat-like ears that amplify sound. Roberts also fixed humans’ backwards retina, which produces a natural blind spot, by borrowing from octopus eye anatomy.

Perhaps most disturbing of all is the baby head poking out of the sculpture’s marsupial pouch. Roberts says marsupial pregnancy would be far easier on the human body and more convenient for parents on the go.

“This could be a human fit for the future,” Roberts says at the end of a trailer for her BBC documentary.

[h/t Motherboard]

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16 Facts About Migraines
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iStock

Unless you suffer from migraines yourself, you may think that having a migraine means having a really bad headache. But debilitating head pain is only one part of the medical condition called migraine disorder. Other common symptoms are nausea, dizziness, fatigue, sensitivity to light and sound, and even temporary blindness. The symptoms and causes of migraine look different in different patients, and researchers are only now beginning to understand what the condition is and how to treat it. Here are some of the most enlightening facts we know about migraine disorder.

1. IT'S THE THIRD MOST COMMON DISEASE IN THE WORLD.

Even if you don’t suffer from migraine, chances are you know someone who does: The disorder affects 14.7 percent of the population, or one in seven people, around the world. In the U.S. alone, roughly 39 million people are affected by the condition. Chronic migraine (experiencing at least 15 headache days per month over a three-month period, with over half being migraines) is more rare, impacting about 2 percent of the world population.

2. WOMEN SUFFER MORE THAN MEN.

Of the one billion people on Earth who have migraine disorder, three-fourths are women. Medical experts suspect this has to do with the cyclical nature of female hormones. According to research presented earlier in 2018, NHE1, the protein that regulates the transfer of protons and sodium ions across cell membranes, is a crucial component of migraine headaches. NHE1 production likely fluctuates a lot more in women than in men. When scientists looked at the brains of lab rats, they found that NHE1 levels were lowest when estrogen was at its peak. In general, female rats also had four times the amount of NHE1 in their brains as males. If the same holds true for people, that could explain why women are not only more likely to suffer migraines in the first place, but why they experience them more frequently and more intensely, and have more difficulty responding to treatment.

3. MIGRAINE TRIGGERS VARY WIDELY.

For doctors and sufferers, migraine triggers can be a source of confusion. They vary from patient to patient and often come from unexpected sources that have no relation to each other. Stress, too much or too little sleep, dehydration, alcohol, and caffeine are some of the most common triggers. Some people get migraines after eating specific foods, like cheese, and others are sensitive to changes in weather conditions like barometric pressure. Some people manage their migraines by pinpointing and avoiding triggers.

4. FOR SOME, AURAS ARE A WARNING THAT A MIGRAINE IS COMING.

Before the nausea, dizziness, and splitting head pain begin, auras warn some people that a migraine is on its way. Less than 25 percent [PDF] of migraine sufferers experience distorted senses, such as numbness or tingling in the hands or face, or blotches of light or darkness disrupting their vision. Auras usually occur 10 to 30 minutes before the migraine develops and last from five minutes to one hour.

5. SYMPTOMS CAN INCLUDE TEMPORARY BLINDNESS …

Unlike migraine with aura, retinal migraine is limited to one eye. Symptoms range from seeing twinkling stars to partial or complete loss of vision. The same eye is almost always affected, and the person typically regains their sight after 10 to 20 minutes.

6. … AND LOSS OF LIMB FUNCTION.

One of the rarest, and scariest, subtypes of migraine is hemiplegic migraine. People with this variant can experience weakness, numbness, tingling, or loss of motor function in parts of one half of their body, including their arm, leg, or face. Though sensations usually dissipate within 24 hours, they can last anywhere from one hour to several days. Sometimes they’re accompanied by typical migraine symptoms, such as head pain, but they can also occur on their own.

7. KIDS GET MIGRAINES TOO.

Migraine isn’t just a problem for adults—up to 10 percent of all school-aged kids are affected by the disorder, with reported cases coming from children as young as 18 months. According to the documentary Out of My Head (2018), migraine is the third most common reason for child emergency room visits. The symptoms of migraine in kids are similar to what’s seen in older patients: They may experience intense head pain, sick feelings, distorted vision, and sensitivity to sound and light. The major differences are that child migraines often develop suddenly and are shorter than they are in adults. In children, it’s not uncommon for the nausea and abdominal pain to feel worse than the actual headaches. Just as some sufferers don’t experience their first episodes until after puberty, some children with migraine grow out of it. According to one study, migraine symptoms disappeared completely in 23 percent of former child sufferers by age 25.

8. MIGRAINE MAY BE HEREDITARY.

For most people with migraine disorder, it runs in the family. Anywhere from 80 to 90 percent of migraine sufferers report having at least one family member who has it as well. If one parent has migraine, there’s a 50 percent chance their child will eventually have to live with migraine—and that risk shoots up to 75 percent when both parents have the condition.

9. MANY VETERANS RETURN HOME WITH MIGRAINES.

Genetics isn’t the only factor that contributes to someone’s chance of having migraine disorder. One study found that after a 12-month deployment in Iraq, 36 percent of veterans exhibited symptoms of migraine. The cause often stems from head or neck trauma sustained from explosions, falls, or other accidents during their service. While post-traumatic migraine goes away in most patients within a few months, in some cases it can develop into a chronic condition.

10. MIGRAINE IS LINKED TO THE "SECOND BRAIN" IN YOUR GUT.

In addition to the part of our nervous system that responds to outside stimuli, humans have an enteric nervous system: the part responsible for regulating digestion. Some medical experts believe that migraine is closely tied to this “second brain.” People with migraine are twice as likely to have IBS as people with tension headaches. Abdominal migraine, where the pain is concentrated in the stomach rather than the head, is one form the condition takes. It's most often seen in children, but it can affect adults as well.

11. DESPITE THE HIGH COST OF MIGRAINE DISORDER, RESEARCH IS UNDERFUNDED.

In 2017, the National Institutes of Health invested $22 million in migraine research. Asthma research received $286 million, breast cancer $689 million, and diabetes $1.1 billion.

12. THE DISORDER COSTS US UP TO $13 BILLION ANNUALLY.

Though migraine isn't life-threatening like these other conditions, it is widespread enough to have a negative impact on society as a whole. Workers with migraine often end up taking a lot of time off from their jobs, which can cost their employers. According to Out of My Head, it’s estimated that 113 million work days are missed annually due to migraine, adding up a to $13 billion loss.

13. MIGRAINE MAY HAVE INSPIRED PARTS OF ALICE IN WONDERLAND …

In the famous children’s book, Alice drinks a liquid that makes her grow many times her size and eats a cookie that shrinks her to tiny proportions. Migraine sufferers may recognize themselves in these passages. Possible symptoms of the disorder include micropsia and macropsia, or perceiving objects to be much smaller or larger than they really are. Some theorize that Alice in Wonderland author Lewis Carroll suffered migraines and wrote his experiences into his story. The book’s connection to migraine is so famous that today the related symptoms are commonly known as Alice in Wonderland Syndrome.

14. … AND PLAGUED A FOUNDING FATHER.

Another famous person from history who likely suffered from migraines was Thomas Jefferson. His symptoms could last for weeks and often appeared during stressful times in his life. There was even an episode that coincided with one of the most important nights of his political career. One night in June 1790, he invited Federalist Alexander Hamilton and Republican James Madison to his home for a dinner party in the hopes of getting his peers to agree on a location for the new U.S. capital. Despite dealing with lingering head pain from a migraine, he successfully brokered the compromise that landed the capital at its current spot on the Potomac River between Maryland and Virginia. In return, Madison agreed that he would not block Hamilton's plan for the federal government to take on state war debt, thus helping establish the young nation's credit.

15. MIGRAINE IS LINKED TO DEPRESSION.

In the U.S., up to 40 percent of people with migraine also have depression. Risk of anxiety, bipolar disorder, and panic disorder are also higher in migraine sufferers. Researchers are still figuring out the connections between mental illness and migraine. While the anticipation of painful symptoms can cause depression and anxiety in some people, experts believe that mental illness is often more than just an effect of living with migraine. The production of the brain chemical serotonin is involved in both migraine and depression. That’s why tricyclic antidepressants designed to increase serotonin levels are sometimes prescribed to treat migraine.

16. A NEW SHOT CAN TREAT MIGRAINE.

Many migraine therapies from the past few decades have been the result of trial and error. Medications designed to treat other conditions, such as antidepressants, epilepsy medicine, and botox, have all been prescribed to migraine sufferers, with mixed results. Earlier in 2018, the first-ever shot made to treat migraines specifically secured FDA approval. The shot, which blocks a peptide linked to migraine, is taken once a month and can improve symptoms or completely eliminate them in some cases. Before the new injection came along, the only other migraine-specific medications patients had to choose from were triptans, which stimulate the neurotransmitter serotonin. They can't prevent migraine, but they can help dampen symptoms by reducing inflammation and constricting blood flow. According to Out of My Head, triptans were first approved more than two decades ago—so new medication options are long overdue.

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