A team of Japanese and Russian scientists has successfully “reawakened” cells from a 28,000-year-old woolly mammoth, according to a study published recently in Scientific Reports.
The cells came from an extraordinarily well-preserved woolly mammoth discovered in Siberian permafrost in 2012 and nicknamed “Yuka”.
Using a process called nuclear transfer, the scientists took nucleus-like structures from Yuka and implanted them into mouse oocytes, which are highly specialized cells that facilitate embryonic development.
The scientists then used a live-cell imaging technique to observe how the structures reacted in their new environment. They saw traces of biological activity.
“I was looking under the microscope at night while I was alone in the laboratory,” 90-year-old Akira Iritani, a co-author on the new study who’s spent years working toward resurrecting the woolly mammoth, told CNN. “I was so moved when I saw the cells stir. I’d been hoping for this for 20 years.”
(For the source of this, and other equally interesting articles, please visit http://www.BigThink.com).
If you want to study a mouse’s natural behaviour, then perhaps it isn’t best to grab the animal and place it in a setting where it’s required to perform a certain task at a certain time. That’s the thinking behind Autonomouse, a cage that’s designed to make life easier for lab mice, and to produce more accurate results in behavioural studies.
Developed by a team at Britain’s Francis Crick Institute, Autonomouse houses multiple mice living in a social group, who are supplied with running wheels, ladders, and unlimited access to food and water. The system can reportedly run for up to 18 months with only minimal human intervention, although there’s no word on how waste-removal is handled.
All of the mice have uniquely-coded RFID chips inserted under their skin. These are detected by a reader device, that’s able to ascertain factors such as each animal’s current weight, its activity level, and how much water it’s drinking.
By Stuart Reynolds, The Conversation –
There are an awful lot of insects. It’s hard to say exactly how many because 80 percent haven’t yet been described by taxonomists, but there are probably about 5.5 million species. Put that number together with other kinds of animals with exoskeletons and jointed legs, known collectively as arthropods — this includes mites, spiders, and woodlice — and there are probably about 7 million species in all.
Despite their ubiquity in the animal kingdom, a recent report warned of a “bugpocalypse,” as surveys indicated that insects everywhere are declining at an alarming rate. This could mean the extinction of 40 percent of the world’s insect species over the next few decades.
What is particularly worrying is that we don’t know exactly why populations are declining. Agricultural intensification and pesticides are likely a big part of the problem, but it’s certainly more complicated than that, and habitat loss and climate change could also play a part.
Although some newspaper reports have suggested that insects could “vanish within a century,” total loss is unlikely — it’s probable that if some species die out, others will move in and take their place. Nevertheless, this loss of diversity could have catastrophic consequences of its own. Insects are ecologically important, and if they were to disappear, the consequences for agriculture and wildlife would be dire.
The Sprawling Kingdom of Bugs
It’s difficult to overstate how many species there are. Indeed, the 7 million estimate above is likely a major underestimate. Lots of insects that look alike — so-called “cryptic species” — are distinguishable only by their DNA. There are an average of six cryptic species for every easily recognizable kind, so if we apply this to the original figure, the potential total number of arthropods balloons to 41 million.
Even then, each species has multiple kinds of parasites which are mostly specific to just one host species. Many of these parasites are mites which are themselves arthropods. Conservatively allowing just one kind of parasitic mite per host species brings us to a potential total of 82 million arthropods. Compared with only around 600,000 vertebrates — animals with backbones — that’s 137 species of arthropod for every vertebrate species.
Astronomical numbers like these caused the physicist-turned-biologist Sir Robert May to observe that “To a good approximation, all [animal] species are insects.” May was good at guessing big numbers — he became the UK Government’s chief scientist — and his quip in 1986 now seems pretty close to the mark.
That’s just diversity, though. How many individual insects would be lost in a mass extinction? And how much might they weigh? Their ecological importance will likely depend on both measures. It turns out that insects are so numerous that even though they are small, collectively, their weight far outstrips that of the vertebrates.
Perhaps the most celebrated ecologist of his generation, the Harvard ant enthusiast E.O. Wilson estimated that each hectare (2.5 acres) of Amazonian rainforest is inhabited by only a few dozen birds and mammals but well over 1 billion invertebrates, almost all of which are arthropods.
That hectare would contain about 200kg dry weight of animal tissue, 93 percent of which would be made up of invertebrate bodies, and a third of that being just ants and termites. This is uncomfortable news for our vertebrate-centric view of the natural world.
The Wriggling Foundations of Life
The role allotted to all these tiny creatures in the grand scheme of nature is to eat and be eaten. Insects are the key components of essentially every terrestrial food web. Herbivorous insects, which make up the majority, eat plants, using the chemical energy plants derive from sunlight to synthesize animal tissues and organs. The job is a big one, and is split into many different callings.
Caterpillars and grasshoppers chew plant leaves, aphids, and plant hoppers suck their juices, bees steal their pollen and drink their nectar, while beetles and flies eat their fruits and devastate their roots. Even the wood of huge trees is eaten by wood-boring insect larvae.
In turn, these plant-eating insects are themselves eaten, being captured, killed, or parasitized by yet more insects. All of these are, in their turn, consumed by still larger creatures. Even when plants die and are turned to mush by fungi and bacteria, there are insects that specialize in eating them.
Going up the food chain, each animal is less and less fussy about what kind of food it will eat. While a typical herbivorous insect might consume only one species of plant, insectivorous animals (mostly arthropods, but also many birds and mammals) don’t much care about what kind of insect they catch. This is why there are so many more kinds of insect than birds or mammals.
Because only a small fraction of the material of one kind of organism is transformed into that of its predators, each successive stage in the food chain contains less and less living matter. Even though efficiency in this process is known to be greater higher up the food chain, the animals “at the top” represent only a few percent of the total biomass. This is why big, fierce animals are rare.
And so it’s obvious that when insect numbers decrease, everything higher up in the food web will suffer. This is already happening — falling insect abundance in Central American tropical forest has been accompanied by parallel declines in the numbers of insect-eating frogs, lizards, and birds. We humans ought to be more careful about our relationship with the little creatures that run the world. As Wilson commented:
“The truth is that we need invertebrates, but they don’t need us.”
Knowing about insects and their ways is not a luxury. Wilson’s friend and sometime colleague Thomas Eisner said:
“Bugs are not going to inherit the Earth. They own it now.”
If we dispossess them, can we manage the planet without them?
3 Itsy Bitsy Reasons Spiders Aren’t Out to Get You
Don’t believe the web of lies.
By Gerhard J. Gries and Andreas Fischer –
It’s early in the morning. The buzzer goes off, you switch on the light, and immediately panic: a large spider sits on your bedroom wall!
Many people suffer from arachnophobia, which is the fear of spiders. Their arachnophobic responses range from subtle discomfort to fumigating their homes. Yet, they have no reason to be afraid of spiders. They just don’t know them well enough. Luckily, fact-based education of arachnophobes helps alleviate their extreme and irrational fear of spiders and enables them to live a less stressful and fearful life.
Education about spiders dispels fear, avoids misconceptions, and instills a sense of appreciation and wonder. Spiders are among the most fascinating and diverse creatures on Earth.
The Roots of Arachnophobia
No one knows the origin of this widespread arachnophobia. With respect to evolution, this phenomenon does not make immediate sense. Avoidance behavior to a perceived threat might have evolved if that threat were to be persistent. But spiders do not pose such persistent threats to humans. This is puzzling to scientists.
There are only a few spiders that could possibly harm us. Most spiders are physically not even able to cause any harm. They are unable to puncture our skin or their venom does not irritate our body tissue.
In Canada, black widow spiders have neurotoxins and can pierce through our skin, but they are not really dangerous to healthy adults (though children and the elderly would need to be watched). Black widows are not aggressive. For them to bite a person, you have to virtually squeeze them. The non-aggressiveness of most spiders, even the venomous ones, effectively renders them harmless.
Fake news about spiders dominate folklore and spread through the internet. For example, the bites of brown recluse spiders can cause necrosis, but it is their harmless cousins, the hobo spiders, that live in Canada. Similarly, false black widows — who look like black widows but are harmless — often find their way into our homes but are less likely to bite us than bees are to sting us when they accidentally fly into our homes.
Unfortunately, many alleged spider bites are misdiagnosed, and the bite symptoms were actually inflicted by other critters or microbes. Such misdiagnoses may even become health-threatening when they prompt inappropriate treatment(s) of the patient. For this reason alone, it is always helpful to capture the alleged biter so that it can be identified, and the patient be treated accordingly.
When encountering a spider at home, many people opt for spraying it with pesticide. But pesticides have long-lasting residual activity, adversely affecting us, our children, and pets. Strategically placed sticky traps (e.g. behind appliances) are a safe alternative to remove spiders and other unwanted creepy crawlies from our homes.
Spiders’ Place in the Ecosystems
By capturing countless insects, spiders play key roles in ecosystems and in agricultural and forestry settings. It is the friendly neighborhood spider that helps protect our crops from insect herbivores. Once we open our eyes to the world of spiders, we will be amazed instead of disgusted and be fascinated instead of fearful. A few stories may serve as examples.
Males of the nursery web spider offer bridal gifts to their future mates. While the female is enjoying her snack, he strives to mate with her before she finishes eating and before she wants him for “dessert.”
The phenomenal jumping ability when they pounce on prey “inspidered” the moniker jumping spiders and is only one reason why they are so fascinating. Entertainingly colorful, extremely photogenic, but no bigger than a thumbnail, the males of some jumping spiders put on a dance-off with remarkable moves to impress females. Jumping spiders use hydraulic pressure to extend their legs, and from a standstill can leap distances up to six times their body length. We humans have to contend with a standstill leaping distance of merely 1.5 times our body length. And just for the record, humans did not invent the hydraulics in our engines; we merely copied the spiders’ invention.
The tiny Darwin’s bark spider is another Guinness record holder. It builds beautiful 25 m wide(!) orb-webs across rivers. Its silk is one of the toughest natural materials known. If we were to weave it into T-shirts, they would be bullet-proof.
Spiders are diverse in shape and behavior. Some spiders build webs which they never leave, while others walk around to hunt, or dig tunnels within which they await prey passing by. Spiders weave many different types of webs, each serving a specific purpose. Other spiders won’t simply wait for prey, they attract it. Bolas spiders produce the female sex pheromone of some moths. This pheromone then attracts male moths that fly towards the spider in anticipation to find a moth mate. When the female spider hears the male moth approaching, she swings her sticky bola and snares him out of the air. The mosquito-terminator spider, on the other hand, spares no efforts to hunt down mosquitoes that have recently fed on blood.
Spiders may be more afraid of us than we are of them: They are not aggressive and would rather be left alone. If we consider the many things we can learn about and from spiders, our fear of them will turn into fascination for spiders.
(For the source of this, and other interesting articles, please visit: https://www.inverse.com/article/53322-why-you-shouldn-t-be-afraid-of-spiders/)