Reading — 2026 Jan–Apr Recall Set 73

The first groups of people to discover New Zealand came from Polynesia. Exactly when these explorers arrived has often been a matter of debate, but today the general understanding is that it was during the 13th century that their canoes eventually landed on New Zealand's shores. In some ways the new country must have seemed like an ideal place to settle: the land was fertile, and thick forests provided firewood, shelter and building materials. Still, life would have been challenging for the different Polynesian tribes, who had to adapt to a new environment. The tribes only began to refer to themselves as Maori, meaning 'ordinary people', when Europeans in search of new opportunities began arriving in the 18th century. To the Maori, of course, the European settlers and sailors were not 'ordinary', but very strange. It was not only a knowledge of canoe-building and navigation that the Polynesians brought to New Zealand. They were also skilled craftsmen. There is archaeological evidence that the tools they produced were of high quality and would have enabled tribes to plant and harvest crops. Craftsmen were also occupied with making weapons such as knives and axes, which were used for both construction and fighting. Interestingly, some crafts that had once been popular in Polynesian islands were no longer done in New Zealand, although researchers are unsure why. Pottery is an example of this, despite the fact that the clay needed to make pots and bowls could easily be found in the new country. The Maori word whakairo can be translated as 'decorative work' — this can refer to bone, wood and greenstone carving. Although Maori carvers were influenced by their Polynesian heritage, they developed their own style, including the curved patterns and spirals inspired by New Zealand plants. The same term can also apply to weaving; the crafting of, for example, woven baskets and mats all required knowledge and skill. Carving greenstone, or pounamu as it is called in Maori, was a long process, requiring great patience. Further, because of this mineral's rarity, any greenstone object, such as a piece of jewellery or cutting blade, was a prized possession. For that reason, it was the few people of high status rather than low-ranking members of a tribe who would possess such objects. As New Zealand had no native mammals except for bats, dolphins and whales, Maori largely had to depend on plants to provide material for their clothing, including their cloaks. Weavers experimented with the inner bark of the houhere, the lacebark tree, but found it unsuitable. But the dried-out leaves and fibres of the flax plant provided a solution. Once a cloak had been woven from flax, it could be decorated. Borders might be dyed black or red, for example. In the case of superior ones made for chiefs or the more important members of a tribe, feathers from kiwi, pigeons or other native birds might be attached. All flax cloaks were rectangular in shape, so had no sleeves, and neither was a hood a feature of this garment. Short cloaks were fastened around a person's neck, and came only to the waist. Pins made of bone, wood or greenstone allowed longer cloaks to be secured at the shoulder; these were a type that were often used for ceremonial occasions. Of course, the construction of the cloaks was influenced by the plant material available to Maori weavers. This meant that cloaks were loose-fitting, and while they protected wearers from New Zealand's strong sunshine, they were not useful during the winter months. A cloak made from fur or wool could provide insulation from the cold, but not so a cloak made of flax. The warriors of a tribe required a different kind of cloak to help protect them. To create these special cloaks, the tough fibres of the mountain cabbage tree were used instead. It is not clear to researchers what the entire process involved, but they believe the fibres were left to soak in water over a period of time in order to soften them and make them easier to weave together. Later, once the whole cloak had been constructed, it would be dyed black. To do this, Maori weavers covered it in a special kind of mud they had collected from riverbeds. This was rich in iron due to New Zealand's volcanic landscape. The particular advantage of these cloaks was that the tough cabbage tree fibres they were woven from could reduce the impact of spear tips during a fight with enemy tribes. It is fortunate that some cloaks from the 1800s still survive and can provide us with further insight into the materials and construction techniques that Maori craftsmen used.

The ants and their agriculture have been extensively studied over the years, but recent research has uncovered intriguing new findings about the fungus they cultivate, how they domesticated it, and how they preserve it from pathogens. For example, the fungus farms, which the ants were thought to keep free of pathogens, turn out to be vulnerable to a devastating mold, found nowhere else but in ants' nests. To keep the mold in check, the ants long ago made a discovery that would do credit to any pharmaceutical laboratory. Leaf-cutting ants and their fungus farms are a marvel of nature and perhaps the best-known example of symbiosis, the mutual dependence of two species. The ants' achievement is remarkable—the biologist Edward O. Wilson has called it "one of the major breakthroughs in animal evolution"—because it allows them to eat, courtesy of their mushroom's digestive powers, the otherwise poisoned harvest of tropical forests whose leaves are laden with terpenoids, alkaloids and other chemicals designed to sicken browsers. Fungus growing seems to have originated only once in evolution, because all gardening ants belong to a single tribe, the descendants of the first fungus farmer. There are more than 200 known species of the attine ant tribe, divided into 12 groups, or genera. The leafcutters use fresh vegetation; the other groups, known as the lower attines because their nests are smaller and their techniques more primitive, feed their gardens with detritus like dead leaves, insects and feces. The leafcutters' fungus was indeed descended from a single strain, propagated clonally, or just by budding, for at least 23 million years. But the lower attine ants used different varieties of the fungus, and in one case a quite separate species, the four biologists discovered. The pure strain of fungus grown by the leafcutters, it seemed to Mr. Currie, resembled the monocultures of various human crops, that are very productive for a while and then succumb to some disastrous pathogen, such as the Irish potato blight. Monocultures, which lack the genetic diversity to respond to changing environmental threats, are sitting ducks for parasites. Mr. Currie felt there had to be a parasite in the ant fungus system. But a century of ant research offered no support for the idea. Textbooks describe how leaf-cutter ants scrupulously weed their gardens of all foreign organisms. "People kept telling me, 'You know the ants keep their gardens free of parasites, don't you?'" Mr. Currie said of his efforts to find a hidden interloper. But after three years of sifting through attine ant gardens, Mr. Currie discovered they are far from free of infections. In last month's issue of the Proceedings of the National Academy of Sciences, he and two colleagues, Dr. Mueller and David Mairoch, isolated several alien organisms, particularly a family of parasitic molds called Escovopsis. Escovopsis turns out to be a highly virulent pathogen that can devastate a fungus garden in a couple of days. It blooms like a white cloud, with the garden dimly visible underneath. In a day or two the whole garden is enveloped. "Other ants won't go near it and the ants associated with the garden just starve to death," Dr. Rehner said. "They just seem to give up, except for those that have rescued their larvae." The deadly mold then turns greenish brown as it enters its spore-forming stage. Evidently the ants usually manage to keep Escovopsis and other parasites under control. But with any lapse in control, or if the ants are removed, Escovopsis will quickly burst forth. Although new leaf-cutter gardens start off free of Escovopsis, within two years some 60 percent become infected. The discovery of Escovopsis's role brings a new level of understanding to the evolution of the attine ants. "In the last decade, evolutionary biologists have been increasingly aware of the role of parasites as driving forces in evolution," Dr. Schultz said. There is now a possible reason to explain why the lower attine species keep changing the variety of fungus in their mushroom gardens, and occasionally domesticating new ones—to stay one step ahead of the relentless Escovopsis. Interestingly, Mr. Currie found that the leafcutters had in general fewer alien molds in their gardens than the lower attines, yet they had more Escovopsis infections. It seems that the price they pay for cultivating a pure variety of fungus is a higher risk from Escovopsis. But the leafcutters may have little alternative: they cultivate a special variety of fungus which, unlike those grown by the lower attines, produces nutritious swollen tips for the ants to eat. Discovery of a third partner in the ant-fungus symbiosis raises the question of how the attine ants, especially the leafcutters, keep this dangerous interloper under control. Amazingly enough, Mr. Currie has again provided the answer. "People have known for a hundred years that ants have a whitish growth on the cuticle," said Dr. Mueller, referring to the insects' body surface. "People would say this is like a cuticular wax. But Cameron was the first one in a hundred years to put these things under a microscope. He saw it was not inert wax. It is alive." Mr. Currie discovered a specialized patch on the ants' cuticle that harbors a particular kind of bacterium, one well known to the pharmaceutical industry, because it is the source of half the antibiotics used in medicine. From each of 22 species of attine ant studied, Mr. Cameron and colleagues isolated a species of Streptomyces bacterium, they reported in Nature in April. The Streptomyces does not have much effect on ordinary laboratory funguses. But it is a potent poisoner of Escovopsis, inhibiting its growth and suppressing spore formation. It also stimulates growth of the ants' mushroom fungus. The bacterium is carried by virgin queens when they leave to establish new nests, but is not found on male ants, playboys who take no responsibility in nest-making or gardening. Because both the leafcutters and the lower attines use Streptomyces, the bacterium may have been part of their symbiosis for almost as long as the Escovopsis mold. If so, some Alexander Fleming of an ant discovered antibiotics millions of years before people did. Even now, the ants are accomplishing two feats beyond the powers of human technology. The leafcutters are growing a monocultural crop year after year without disaster, and they are using an antibiotic apparently so wisely and prudently that, unlike people, they are not provoking antibiotic resistance in the target pathogen.

Why do we clap at the theatre? Did you know that the average speed of our claps ranges from 2.5 to 5 claps per second? Some have said that clapping is like high-fiving yourself in a positive response to something that someone else has done. Clapping is the most common sound that we, as humans, make, other than using our vocal cords. We do it as a social gesture to show approval and admiration in groups, in crowds, or by ourselves, and most often in settings where we are presented with something like a show or performance. But what is the logic behind clapping? It crops up in every culture across the globe, and is one of the most universal means of communication. Let's take a deep dive into the history of applause. A primitive action The action of clapping is actually quite a primitive one, initially being used in response to being aroused. A recent study showed that when an individual applauds, it actually has very little to do with that person's own opinion of the quality of the performance they have witnessed; it has more to do with the feeling of belonging in the group who have all experienced something collectively. Haven't you ever heard someone say that they're "just clapping to be polite"? Or when you applaud because everyone else is clapping, even if you're not really sure what's going on yourself? Don't worry, we won't tell anyone! Applause in ancient times In comparison to vocalizing approval through speech, clapping is easier, louder, and more anonymous, especially in crowds. You can't tell much about a person from their clap, like their gender, age, or origin. Clapping is even considered more democratic, since stomping your feet can be seen as aggressive or disruptive, and not everyone can snap their fingers. Way back in the 6th century BC, lawmaker Kleisthénes of Athens decided that audiences should clap to demonstrate their approval of their leader, since there were too many people to determine their approval one by one. Through this came "applause," the unified voices of all these people, communicated through their clapping together in admiration. A few hundred years later, in the 4th century BC, came the claqueur. A claqueur was a person whom a theatre could hire to clap, cry, or laugh at the right moments in order to influence the other audience members' reactions. In 4th-century Athens, competition was fierce between comedians, and claqueurs became a common tool used to sway the decision of the judges and, consequently, to bag the award for best performance. In the Roman Empire, the practice of using applause as a means of influence was applied to politics, and claqueurs were found in both courts of law and private art demonstrations. Emperor Nero even established a school of applause with a claque of thousands of knights and soldiers following his auditorium tours! Applause in the 18th century The history of clapping has a unique role in France and French venues as well. In 18th-century France, the claque had a strong presence as an organized body of professional applauders and influencers. They frequently attended theatres in order to sway the responses of the spectators, and were paid by the production and by the actors in the form of free tickets. It was a highly organized affair, with certain claqueurs assigned to laugh loudly during comedic portions, others to shed a tear for a melancholic performance, and even claqueurs designated to comment their appreciation of a play or speech to fellow audience members! What about today? Nowadays, however, the days of claqueurs are over, and all you'll find in Parisian playhouses is true, rapturous applause. We do still find some traces of the practice, however; the remnants of the claqueurs linger on television show sets and radio programs, in the form of applause symbols to indicate to the audience when they should be clapping, or even canned applause and laughter. It is also interesting to note that there are appropriate times and places for applause. It is considered perfectly normal to applaud a politician as he takes the stage before he even gives a speech, as a sign of approval and in recognition of past accomplishments. In a religious setting, however, applause is very rarely heard. During a play, it would be deemed rude to begin applauding in the middle of the performance, although one often hears clapping throughout an opera in appreciation of a particularly difficult piece of music. Applause can even evolve into higher gestures of approval - a standing ovation, anyone? Overall, it's safe to say that clapping has now evolved into an expectation and standard of behaviour. It's no longer a biological or sociological reaction, like it once was in primitive times, nor is it any longer manipulated by private performance directors as a means of influence. The act of applause and clapping along with other people following a performance of any kind has become a social norm with a long list of historical influences. Isn't it interesting how one simple gesture can be used as a means of political persuasion, and to demonstrate the utmost admiration? That alone deserves a round of applause!