Tea with Science

Bacteria use CRISPR for defence; what will we do with it? From the potato to the human, a new tool can manipulate genes to change organisms with a combination of accuracy, speed, flexibility and low cost that we've never seen before. It is so easy to use there's even a do-it-yourself kit . That's right - everyone can now tinker with genes. Imagine what the experts can do. Should we be scared or excited? The new technique could lead to organ transplants from pigs , population-wide sterilization of malaria-carrying mosquitoes , the eradication of genetic disorders from an entire family line, a cure for HIV , and the great auk brought back from extinction after nearly 200 years. Great auk, currently extinct Image: John Gerrard Keulemans That is the potential of CRISPR (“crisper”), a tool that is used in nature by bacteria to defend themselves against viruses. If a bacterium survives a viral attack, it can sometimes take a part of the viral DNA and s...

To children and rats alike, the sparkly rocks of Central Park represent scampering opportunities. To tourists, they represent resting opportunities before the hard business of sightseeing resumes. The rocks of Central Park are part of the NYC experience for so many people, but however permanent those rocks may seem, they are themselves evidence that nothing lasts forever. Half a billion years ago, the oldest rocks of today’s city, Fordham Gneiss, lay south of the equator in a shallow ocean just off an early continent. Sea creatures lived and died there, leaving shells behind that collected on the ocean floor, slowly forming beds of limestone. Mud and more sediments, together with volcanic ash from a nearby string of volcanic islands, compressed over time to form a layer of shale. The volcanic islands were a sign that the continents were on the move. In an almighty slow-motion crash, the volcanic islands collided with NYC's early continent. Land crumpled, sending up a moun...

Night has fallen in the tropics. Beneath the ocean surface, a soft body and swaying tentacles reach up from a skeletal cup. This is a polyp, the individual of the coral reef. Its tentacles are armed with stinging tips, ready to bring any passing plankton into the body. The polyp is not alone. Its colony of identical swaying polyps may have been around for centuries. Panning further out, the colony is part of a reef that could be thousands of years old and more than a thousand kilometres long. Credit:  NOAA /Julie Bedford A generation ago, coral reefs were thought to be immutable. Colonies might occasionally perish at the force of a hurricane or predator, but the overall reefs would carry on, providing a quarter of marine life with food or shelter, providing developing countries with a quarter of their fish catch, providing shorelines with storm protection, and providing jobs in tourism. Then in 2006, two common corals were listed as threatened. In little more than the decad...

17th February, 2018 Mid-Hudson Valley, New York Snow is promised this evening, and we are watching for those first chubby flakes to break the dark. When they come, they’ll drift in soft clusters, they’ll stick to our woolly gloves, and the kids will look skywards to catch them on their tongues. So we imagine. Stellar plate, by  Alexey Kljatov  /  CC BY-NC 2.0 The reality may be different: wet globules sticking to our eyelashes, pellets hurling themselves into our down-turned faces, or something so fine that we won’t at first be certain whether it’s rain or snow. What’s happening up in those clouds right now? What type of snow are they making? All snowflakes, the beautiful and the plain cold ugly, start out when water vapor crystallizes around a speck of dust or pollen in a cloud. The water molecules arrange themselves into repeating hexagons, one water molecule at every corner of every hexagon. Different crystals take different structures,...

Imagine yourself a space tourist, standing on the moon and looking back at those fluff-white clouds gliding across the Earth. You can gaze on that view as long as you like, but you’ll never see Earthrise nor Earthset from the surface of the moon. The Earth will stay in one place and instead of watching it travel across the sky, you'll get to watch it spin. Our 1st glimpse of the far side, 1959/ Luna 3 , by  OKB-1 You would see the Earth spin from the moon because the moon takes the same time to make one full rotation as it takes to orbit the Earth, a little over 27 days. As a result, the moon always shows us the same face. It’s a leisurely rotating pace compared to the Earth’s whirling, 365 times for each single orbit around the Sun. Long ago, when the moon was young, it span a lot faster. As it did so, the Earth’s gravity was felt more strongly on whichever part of the moon was facing the Earth, just as the moon’s gravity tugs at the Earth’s oceans to produce tides. Th...

Plant an apple seed from the juiciest apple you ever ate, then sit back and wait ten years. You might move away in the meantime, but you won’t forget your little apple tree. Take a pilgrimage to see the result of your patience: ripe apples. They’ll look a little different from that memory of ten years ago, but bite into one and… euugh! Spit it out and stare in horror. Mutsu - my favourite:-) The saying is wrong; the apple always falls far from the tree. Every seed in every apple contains a different combination of genes from its two parents, and only occasionally does the crossing result in a tree with a good tasting apple. It’s a problem that was solved thousands of years ago by grafting. Apple growers discovered they could dispense with seeds by inserting a twig with a bud from a desired tree into the base of a less desirable tree with the top cut off. The resulting apples, barring mutations, would all be as delicious as those from the first tree. It was an early form of clon...