‘Amazing science’: researchers find xenobots can give rise to offspring. Some species do it in pairs, some without knowing the other parties involved, and some even do it on their own: when it comes to replication, nature is nothing if not versatile.
Now researchers say they have found that clusters of frog cells can undergo a form of replication never before seen in plants or animals. The spherical clumps, known as xenobots, can give rise to “offspring” by sweeping up loose cells and swashing them into yet more clusters. “These things move around in the dish and make copies of themselves,” said Prof Josh Bongard, of the University of Vermont, a co-author of the research. Xenobots were first announced last year, and are what are known as “living robots”– synthetic lifeforms made by taking a few thousand cells from frog embryos and assembling them into clusters about 1mm in size. Xenobots have no digestive system or neurons, and naturally fall apart after about two weeks. One of those ways is the production of offspring. But there is a hitch. South Korea trials robots in preschools to prepare children for high-tech future.
Seoul has started trialling pint-sized robots as teaching aids in kindergartens – a pilot project the city government said would help prepare the next generation for a hi-tech future.
The “Alpha Mini” is just 24.5 centimetres tall and can dance, lead sing-a-longs, recite stories and even teach kung fu moves as children mimic its push-ups and one-legged balances. “The robots help with the kids’ creativity,” teacher Byun Seo-yeon told Agence France-Presse during a visit to the bright and busy Maru nursery in Seoul. The robot’s eyes wink and blink – and its pupils become heart-shaped during conversation. With a camera on its helmet, it takes photos that are instantly sent to a tablet for viewing. “In the future, knowing how to manage AI and related tools will be very important,” Han Dong-seog, from the Seoul government’s childcare division, told Agence France-Presse.
“When I tell it to sing, it sings well. Kambrische Explosion. Als kambrische Explosion, kambrische Artenexplosion oder auch kambrische Radiation (vgl.
Adaptive Radiation) wird das fast gleichzeitige erstmalige Vorkommen von Vertretern fast aller heutigen Tierstämme im geologisch winzigen Zeitraum von 5 bis 10 Millionen Jahren zu Beginn des Kambriums vor etwa 541 Millionen Jahren bezeichnet. Die grundlegenden Körperbaupläne vieler mehrzelliger Tierstämme, die seitdem die Erde bevölkern, sind in Gesteinen dieser Epoche erstmals überliefert.
Das erste Auftreten von Vielzellern datiert man auf 2,1 Milliarden Jahre vor unserer Zeit (Gabonionta).[1][2] Wie alle anderen Fossilien vor dem Mesoproterozoikum handelt es sich um schwer interpretierbare Zellkolonie-artige Bildungen ohne sicheren Bezug zu späteren Organismen. Heute kann man diesen langen Zeitraum auch ohne Zuhilfenahme von Leitfossilien besser aufgliedern (→ Geologische Zeitskala).
Die präkambrische Tierwelt[Bearbeiten | Quelltext bearbeiten] ‘Hangxiety’: why alcohol gives you a hangover and anxiety. If you are looking forward to your first stiff drink after a dry January, be warned: it may feel bittersweet.
You may feel you deserve an alcoholic beverage after toughing it out all month – but have you forgotten what it feels like to wake up haunted by worries about what you said or did the night before? These post-drinking feelings of guilt and stress have come to be known colloquially as “hangxiety”. But what causes them? David Nutt, professor of neuropsychopharmacology at Imperial College, London, is the scientist who was fired in 2009 as the government’s chief drug adviser for saying alcohol is more dangerous than ecstasy and LSD.
I tell him I have always assumed my morning-after mood was a result of my brain having shrivelled like a raisin through alcohol-induced dehydration. Alcohol, he says, targets the Gaba (gamma-aminobutyric acid) receptor, which sends chemical messages through the brain and central nervous system to inhibit the activity of nerve cells. Scientists close to first sighting of black hole in the Milky Way. Astronomers attempting to capture the first images of the black hole at the heart of the Milky Way have given early hints that the ambitious project has been successful.
The observations, by the Event Horizon Telescope, are expected to be unveiled in the spring in one of the most eagerly awaited scientific announcements of 2019. Now, a senior scientist on the project has said “spectacular” data was gathered during observations of two black holes, including Sagittarius A* at the centre of our own galaxy. “We managed to get very high-quality data at the very high resolutions necessary to observe the [black hole’s] shadow, if it’s really there,” said Sera Markoff, a professor of theoretical astrophysics and astroparticle physics at the University of Amsterdam, who co-leads the EHT’s Multiwavelength Working Group. Until now, though, a black hole has never been directly observed. So is it nature not nurture after all? There are few areas of science more fiercely contested than the issue of what makes us who we are.
Are we products of our environments or the embodiment of our genes? Is nature the governing force behind our behaviour or is it nurture?