1. If nanotechnology sounds too far-fetched, looking at what geckos can do might be a good starting point. These lizards could quickly snatch the champion title in a climbing competition should there be one. Watching them climb upside down on a horizontal pane of glass, one can't help thinking that Spiderman should really have been called Geckoman. Without breaking a sweat, they can easily hang from a single toe, and they do so by pure adhesion, not by sticking a toe in a hole or by curling it around something they can grip. Scientists estimate that if all its toes touch the glass, it could take the weight of a 100kg person suspended below it, of course, under the condition that the rest of the body were strong enough. Although each toe is equipped with a tiny hook-like claw at the end, these are almost useless on the glass. The secret to geckos' superpower lies in the amazing structure of the skin of their toes.

2. [I] Over the past 15 years, scientists have been working tirelessly to try to unlock the secrets of the stickiness of gecko toes and come up with a way to artificially reproduce the same structure of nano-hairs. [II] This is one example of research in the field widely known as nanotechnology. In this field, the technology developed can be measured in a few nanometres (one nanometre is a millionth of a millimetre), meaning that how it works can only be visible when seen under a microscope. [III] It was the American theoretical physicist Richard Feynman who set the quest in motion at the beginning of the 1960s, but the "nano" catchphrase was coined in the 1990s by Dr. Eric Drexler, who spurred scientists on through a series of speeches and a book entitled "Engines of Creation: The Coming Era of Nanotechnology". [IV]

3. According to nanoscientists, one application of nanotechnology that will make the biggest splash in the media will be the gloves and the boots that will allow rock-climbers to take their sport to previously undreamed of heights. But the technology could also be used in surgery to keep the edges of wounds together without the need of stitches. There will also be a huge potential in the manufacturing sector to stick millions of components together tighter than ever before without glues or screws.

1. Extreme habitats are environments where most life, including humans, cannot survive. [I] These areas can be either very cold or very hot. [II] For example, polar regions are extremely cold, with temperatures often falling below 5°C. [III] Despite these harsh conditions, some microbes are able to live and even thrive in these areas. [IV] These bacteria are a type of psychrophile, which are microorganisms that grow best at temperatures of 15°C or lower.

2. On the other hand, some of the most extreme habitats are hot, with temperatures reaching over 40°C. These places are often near geothermal activity, such as deep-sea vents and hot springs. In 1966, microbiologist Thomas Brock discovered that microorganisms were surviving and growing in the hot springs of Yellowstone National Park. These organisms, known as thermophiles, require high temperatures to live. Deserts are also considered extreme hot environments. For example, the sidewinder snake has adapted to survive in the desert by moving in a way that only parts of its body touch the hot sand, reducing its exposure to the heat.

3. Organisms that survive in these extreme conditions can teach scientists important lessons. One example is the wood frog in Alaska (Lithobates sylvaticus). During winter, these frogs freeze completely, but when spring comes, they thaw and continue their lives. Scientists discovered that the frogs create chemicals that protect their organs from ice damage. This finding can help researchers develop methods to extend the preservation of human organs. Such advancements may be crucial for improving organ transplants.

4. Another remarkable organism is the tardigrade, also known as the water bear. This tiny creature can survive in many extreme environments, such as high mountains, deep oceans, and cold Antarctica. The water bear has even survived in space. By studying these organisms, scientists hope to learn more about life on other planets, such as Mars.

1. The idea of bringing extinct animals back to life, or "de-extinction," has become a topic of growing interest in recent years. With advances in genetic technology and cloning, many believe that resurrecting extinct species could help restore ecosystems and offer valuable scientific insights. However, the idea raises significant debates, especially when considering ethical, ecological, and practical concerns.

2. One argument in favor of de-extinction is that it could help restore ecosystems that have been altered by human activity. For example, the woolly mammoth once played a key role in maintaining the balance of the grasslands by controlling tree and shrub growth. Reintroducing such species might help to restore ecosystems that have been negatively affected by their absence. Additionally, scientists argue that de-extinction could help us understand more about extinct species and their roles in the environment, offering insights into past ecosystems and the causes of their decline.

3. Despite these potential benefits, there are several challenges and risks associated with de-extinction. [I] First, many of the environments in which these species once thrived no longer exist. [II] Even if these animals were successfully revived, there is no guarantee that they would be able to survive in today's different ecosystems. [III] Another concern is that focusing on reviving extinct animals could take attention and resources away from saving species that are still alive but at risk of extinction. [IV] With biodiversity rapidly declining due to habitat destruction, climate change, and human interference, some argue that we should focus on protecting the species we still have, rather than attempting to bring back those that have already vanished.

4. While de-extinction presents exciting possibilities, it is fraught with challenges. Instead of focusing on bringing back extinct species, efforts should prioritize the protection of existing species and ecosystems. This would ensure that the future of our planet's biodiversity remains secure.