Plants convert only 1-2% of the sunlight they absorb into chemical energy, yet the total energy produced globally through photosynthesis is approximately 130 terawatts; that’s around 8 times more than current human energy consumption. This illustrates the enormous potential for harnessing even a fraction of sunlight to power renewable technologies, such as artificial photosynthesis, which could revolutionise the way we generate and use energy.
Nature’s process of converting sunlight, carbon dioxide and water into energy has long been a subject of interest for scientists, as it holds the potential to become a sustainable and carbon-neutral energy source. However, while progress has been made in laboratory settings, scaling up this technology to a level where it can replace conventional energy sources is still a significant challenge.
The technology behind artificial photosynthesis operates in two main stages. The first involves light absorption, utilising photo-electrochemical (PEC) cells made with semiconductor materials like titanium dioxide. These cells imitate the role of chlorophyll in plants by capturing sunlight. In the second stage, the PEC cells convert the absorbed light into electrical energy. This energy is then used to split water molecules into hydrogen and oxygen while transforming carbon dioxide into hydrocarbons.
Significant challenges remain in enhancing the stability and efficiency of the materials used in photo-electrochemical (PEC) cells to capture more sunlight at a reduced cost. One of the primary limitations in this area has been the reliance on rare materials and the complexity of the systems required. Even more pressing, though, is the scalability of this technology to meet global energy demands. To convert sunlight into storable fuels efficiently, integration with existing energy infrastructure is essential – a complex task requiring substantial advancements in both technology and economic feasibility.
Progress in artificial photosynthesis has advanced rapidly, driven by breakthroughs in nanotechnology, materials science and artificial intelligence. Researchers at the University of Cambridge have, for example, developed an ‘artificial leaf’ that mimics natural photosynthesis, producing syngas – a sustainable liquid fuel alternative to petrol. Additionally, scientists at the Daegu Gyeongbuk Institute of Science and Technology in South Korea have made significant strides in solar hydrogen production using advanced photo-electrochemical (PEC) cells. The integration of artificial photosynthesis with other renewable technologies, such as solar panels, has also led to the development of hybrid systems capable of producing both hydrogen fuel and electricity.
While artificial photosynthesis is not yet commercially viable on a large scale, the progress achieved so far holds significant promise. As both governments and private sectors continue to invest in green technologies, it could soon play a pivotal role in addressing the world’s energy and environmental challenges.
One of nature’s most radiation-resistant microorganisms, Deinococcus radiodurans (pictured), can survive 5,000 times the amount of radiation that would kill a normal person. Methanogens, on the other hand, can survive entirely without oxygen. They are both known as extremophiles, mainly microbes, which thrive in the most unexpected and extreme environments, offering insights into the origins of life in conditions dominated by such hostile surroundings. Scientists study the remarkable mechanisms of these microbes with the aim of developing innovative technologies and materials.
Extremophiles have developed specialised adaptations that enable them to survive in conditions typically considered inhospitable to life. Microaerophiles can survive with little to no oxygen, while halophiles can survive in high saline environments such as salt flats. Researchers have also found microbes from the Firmicutes phylum at least 13 feet below the Atacama desert that are able to survive in such conditions and could lead the way in the search for life on Mars.
Thermophiles can survive in hot environments exceeding 100C while psychrophiles prefer sub-zero temperatures. Thermus aquaticus, a bacterium that thrives in water above 70C was discovered at Yellowstone national park. Its enzymes were found to remain functional at extreme temperatures, a discovery that ultimately paved the way for the development of PCR-based COVID-19 tests nearly 50 years after they were first detected.
The remarkable adaptability of extremophiles begins at the cellular level, often driven by biochemical and structural adaptations. Some microbes can produce specialised enzymes and proteins while modifying their membrane composition to become more rigid or flexible, allowing them to survive extreme temperature fluctuations. Tightly folded protein structures, for example, are able to withstand high temperatures without denaturing while lipids and fatty acids can help make cell membranes rigid and heat resistant.
Enhanced DNA repair systems can help microorganisms withstand high radiation environments. Some extremophiles safeguard their DNA by utilising histone-like proteins to enhance its stability and employing highly efficient repair mechanisms to fix any damage.
The unique abilities of extremophiles have made them invaluable in fields like medicine, biotechnology, industry, agriculture and space exploration. As we saw above, the enzyme Taq polymerase, derived from Thermus aquaticus, is used to amplify DNA in the Polymerase Chain Reaction (PCR) included in COVID-19 testing. Extremophiles are also crucial in bioremediation, where their ability to degrade toxic substances can aid in the cleaning up oil spills or soil contamination. Furthermore, studying how certain extremophiles endure high radiation and extreme vacuum conditions can aid in the development of technologies for long-term space exploration.
The human microbiome includes trillions of microorganisms such as fungi, yeast, bacteria and viruses, most of which are located in our gastrointestinal tract. When these healthy biomes are disrupted and become imbalanced, a “pathobiome” may form which can cause numerous health problems. Traditionally, scientists believed that the brain was a sterile environment, protected by the blood-brain barrier. However, recent research has suggested that the brain may possess its own unique microbiome that could impact the health of the brain and is redefining our understandings in neuroscience.
In advanced imaging and molecular studies of brain samples from those with Alzheimer’s and those without, researchers found evidence of microflora in all samples. However, there was up to seven times more bacteria and different profile proportions in the Alzheimer’s samples. Many of these microbes are thought to have functional roles, perhaps as immune system regulators or in sustaining our metabolic health. But how can microorganisms enter across the blood-brain barrier, a filter designed to keep out pathogens and toxins? One theory is that the blood-brain barrier becomes compromised and damaged due to ageing or inflammation.
Once microbes have entered the brain, it is thought that in an imbalance in microfauna can lead to the inflammation. If this inflammation becomes too extreme, it can lead to the damage of brain cells that lead to neurodegeneration. A known characteristic of Alzheimer’s is the buildup of toxic proteins that include beta amyloid and tangles of tau. These proteins activate the brain’s immune cells which are known to cause inflammation as a response mechanism. If microorganisms are causing inflammation through this triggering of immune responses, it can signal a link between their presence and an increases in the risk of Alzheimer’s disease. It is also believed that microbes in the gut can have an impact on the health of the brain – known as the gut-brain axis. New research is investigating how gut bacteria influence the brain through the nervous and immune systems.
If it is proven that microbes really do influence neurodegenerative diseases, new treatments could help to stem their impact, such as probiotics or specialised diets. Although in its early stages, a promising study showed that treating mice with antibiotics weakens the signs of Alzheimer’s by decreasing the amount of amyloid-ß (Aß) peptides in the brain. This suggesting that microbes were indeed playing a part in their neurodegenerative decline.
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Understanding the environment is paramount to protecting the planet, but with the overload of information available, some terminology can get lost along the way. ‘Biodiversity’, for instance, is a staple buzzword when it comes to climate change, but what does it really mean?
Quite simply, biodiversity means ‘the variety and abundance of the world’s plants and animals’ (Flora & Fauna, 2024). On a global scale, biodiversity might refer to an entire species at risk of extinction, while on a local scale, a rainforest is home to tens of thousand different species – this is a biodiverse environment. The rainforest is rich in biodiversity, whereas a plantation with only one type of tree would lack biodiversity, as it may not support many other species.
A reduction in the number of plant and animal species is known as biodiversity loss. The extinction of species worldwide is an indicator of biodiversity loss and currently, it’s declining faster than ever before – some scientists even believe the Earth is experiencing its sixth mass extinction. Species extinction is just one essential element of biodiversity loss, but it also results in deprivation of the services that natural ecosystems provide to humans, such as the oxygen we breathe or the pollination process.
According to Earth.org, there are four key causes of biodiversity loss. While natural processes can result in permanent changes to the environment, human activity since the Industrial Revolution has expedited the loss. Habitat loss due to land and forest clearing is a significant driver. The human development of land and expanding industries has caused the loss of millions of hectares of trees and their associated ecosystems. This means that natural habitats, such as forests, are declining, having a catastrophic impact on the animals, plants and insects they are home to.
Wildlife trading causes nearly 30,000 species to become extinct every year. Wildlife and exotic pet trading, as well as animal poaching, often target vulnerable species putting them at greater risk of extinction. Overfishing means that due to the demands of the commercial fishing industry, humans fish at a higher rate than stocks are able to replenish. Despite the regulations in place, many marine species are in decline.
Climate change is perhaps most widely known as contributing to biodiversity loss and environmental damage, as the human dependence on fossil fuels and the consequent greenhouse gas emissions have caused climate change. The rising temperature across the globe means that species cannot move or adapt quickly enough to keep up with the changes, putting millions of species at risk of extinction.
Fundamentally, biodiversity is the planet’s superpower; the Earth’s capability to home so many living things.
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Every year, salmon undertake what might seem like one of the most illogical journeys in nature. They leave the sea and swim up estuaries, returning to the rivers where they were born, a journey that can span hundreds of miles. It typically takes salmon about 14 to 21 days to swim upstream to their spawning grounds, guided by the memorised scent of their birthplace and the Earth’s magnetic field . They’re engaging in an epic pilgrimage back to their natal rivers—the exact location where they were born — to spawn, reproduce, and start the whole lifecycle again.
This behaviour is a true call of nature, and an extraordinary one at that, as most salmon die of exhaustion once spawning is completed. This journey is partly explained by the Salmon’s anadromous nature, meaning they are born in freshwater, migrate to and live in the saltwater sea during adulthood, and return to freshwater to spawn. As a point of note, Sturgeon are also known to exhibit this extreme migratory behaviour. This anadromous behaviour of Salmon is controlled by their intrinsic biological clock that triggers spawning behaviour which is vital for the continuation of their species. But this still begs the question: Why not spawn near the river mouth if they only seek freshwater? Why make the exhausting and nearly impossible journey back to their birthplace just to reproduce? It seems to be an extreme course of action without obvious justification!
Experts explain that estuaries and river mouths are not ideal for spawning because they are often murky, silt-laden environments with low oxygen levels. These areas are also partially saltwater and are wide, exposed spaces that serve as prime hunting grounds for predators. In contrast, the freshwater areas further upstream are much more suitable for spawning, and progeny survival rates are much higher.
These upstream environments are rich in dissolved oxygen, which is essential for both the adult salmon and their eggs for different reasons. The well-oxygenated water helps salmon endure the grueling journey, which can be compared to running multiple marathons in succession.
After the eggs are laid far upstream, they benefit from the highly oxygenated water, which boosts their survival and maturation rates. Additionally, there are fewer predators in these areas, especially since salmon typically lay their eggs in gravel beds in shallow stretches of rivers, which larger predators cannot easily access.
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With access to better food and health care, people are increasingly living longer; the global average life expectancy in 2024 is 73 – over double the number from 1900. Technology is playing a large part in future life expectancy and later quality of life, with healthcare innovations such as personalised medicine and digital robots shaping the future and challenging the perceptions of what it is to become old.
Wearable technology has become extremely fashionable as people become conscious of adopting healthier lifestyles. Older generations are becoming more digitally savvy and are taking advantage of such devices to measure their vital signs such as heart rate and blood pressure. Many devices are now available with a personal emergency response systems (PERS) which enable the user to send an alert to a primary caregiver or emergency services; some can also detect falls and accidents.
These devices act as a useful remote monitoring system and were hugely popular during the COVID-19 pandemic. They enable less hospital trips and caregiver visits as health vitals can be remotely tracked. Online services have also allowed older generations to become more independent with the convenience of digital health record access and medical appointment scheduling.
AI and personalised medicine are making impactful changes to the quality of life in older individuals by offering personalised diets, exercise routines and medications. Using advanced software, genetic information and lifestyle factors can be considered to make specific recommendations for more effective treatments that have fewer side effects. Big data can use statistics from the general population to help to identify patterns and trends that predict illnesses before they arise.
As older individuals become less physically able, home technology such as voice assistants and smart home hubs will play a part in everyday life such as operating lights and curtains or ordering shopping and medications. Mobility aids such as smart walkers and wheelchairs are becoming equipped with enhanced stability, stairclimbing capabilities and posture management features, enabling added comfort and accessibility.
Robotic aids for the elderly are also becoming popular to help maintain a sense of independence and improved quality of life. Loneliness is an increasing factor amongst the older generation. Human robotic companions can provide social interaction and emotional support that help increase mental health and wellbeing while service assistant robots can help ease physical tasks such as loading the dishwasher and preparing food and drinks.
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Agging is an ongoing process with gradual physiological changes that lead to senescence – a decline in biological function and increased vulnerability to metabolic stresses. Theories of ageing have been debated since the ancient Greeks. There is currently no one theory that covers all the different aspects of ageing; many theories fall into the programmed (biological clock) and damage or error related categories. Some of the popular theories around ageing include genome damage to DNA, telemere shortening, misfolding of proteins, cell senescence and stem cell exhaustion.
During genomic instability, our DNA can become damaged due to external factors (such as UV light exposure) and internal factors (such as mutations). Damaged DNA can affect gene expression and transcription which can lead to dysfunctional cells.
Telemeres are the caps contained on the ends of DNA strands that protect them from damage. With each cell division, the length of the telomeres shorten; cell apoptosis (death) can eventually occur if the telomeres become too short.
Proteostasis is the process involving the folding, chaperoning and maintenance of protein function which keeps cells healthy. As protein damage occurs (e.g. through oxidation) over time, chaperones can become distracted with irreversibly damaged proteins, leading to an accumulation of newly misfolded proteins.
Cell senescence occurs when old and damaged cells cease to replicate. Senescent cells release senescence-associated secretory phenotype (SASP) molecules which, in accumulation, can alter and disrupt the surrounding environment and cause inflammation and cancer.
Stem cell exhaustion can occur when our stem cells lose their ability to divide or are unable to be replaced. Stem cells are vital to tissue regeneration and their loss contributes to the ageing process.
As technologies, medicine and our understanding of the ageing process improve, so has the average human lifespan. People are living longer and this trend is predicted to continue into the future.
There is currently a wide range of scientific research being undertaken to reverse the ageing process, with a focus on its different aspects. T cells, a type of white blood cell which defend our bodies against bacteria and viruses, are being researched and reprogrammed to target cancer cells. Senolytics are specific drugs that has been synthesised to target and remove senescent cells and their damaging SASP molecules. Telomerase activation works on the theory that using drugs to induce an enzyme called telomerase to extend chromosome telomeres will effectively increase an organism’s lifespan.
The ageing process is a topic of high scientific interest, although it is complicated and involves many factors which are not yet fully understood. It is thought, for example, that telomeres act as a biological safety device to stop cancerous cells from proliferating. While we are not yet able to reverse ageing, significant progress has been made to allow the slowdown or the partial reversing of it.
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Wetlands have in the past been considered as wasteland to be repurposed, but are now considered one of the most productive ecosystems in the world. They are found all over the world in a variety of forms such as estuaries, flood plains and peat bogs and serve a diverse range of purposes to help manage our environment, biodiversity and water channels.
It is estimated that 40% of all of our plants and animals rely on wetlands, with 200 new species discovered in freshwater wetlands every year. Coastal wetlands such as mangroves are considered among the most biologically diverse places on Earth.
Wetlands act as nature’s water filters, removing sediment and absorbing pollutants – as much as 60% of metals and 90% of nitrogen. This water purification process creates the right conditions for life to thrive and supports the livelihood for one billion people.
Wetland can act as waterway regulators, absorbing excess water from river floods to reduce flash flood damage while creating a slow release to feed rivers during periods of draught. Mangroves also act as important storm shields to protect 60% of the worlds population living near the sea from coastal flooding.
Wetlands can help to slow down the impact of climate change by absorbing large amounts of atmospheric carbon – up to 50 times more carbon than rainforests. Plants absorb carbon dioxide and decompose slowly in the anaerobic waterlogged conditions, effectively acting as a carbon sink.
It is estimated that 35% of our wetlands have been destroyed since 1970 and continue to disappear at a rate three times faster than forests. Pollution, intensive farming, urbanisation and global warming are some of the biggest threats to the future of these vulnerable habitats. Wetland biodiversity loss is a major concern while an increase in global warming will cause wetlands to reverse their carbon sequestration effect.
In 1971, the Convention of Wetlands was passed to specially protect wetlands to protect against loss and degradation. Unlike woodlands and rainforest, new technologies mean we can create new wetland in a matter of years. Nature has also played a part, with beavers recorded as actively helping to replenish these areas through the creation of shallow ponds and complex wetland habitats. Through our conservation efforts and sustainable practices, there is hope that we can once more re-establish these vital areas on Earth.
Symbiosis is defined by the interactions between two organisms of different species. The word originates from two Greek words meaning “with” and “living” and describes the relationship that may or may not be beneficial to both organisms. There are four main symbiotic relationships in nature: mutualism, commensalism, parasitism and competition.
In mutualism, both species benefit from the relationship. This could mean that they thrive better together (facultative mutualism) or could simply not survive without each other’s presence (obligate mutualism).
Perhaps the most well-known example of mutualistic symbiosis is the relationship between bees and flowers. In return for receiving sugar-sweet nectar, bees help to pollinate the plants which may have otherwise not been able to reproduce. This happens because the pollen sicks to the bees legs when they feed; some bees have even developed special structures on their legs called pollen baskets to help the process.
In commensalism, one species benefits while the other does not, but is not harmed in the process. This relationship normally takes place between a larger host organism and a smaller beneficiary organism who gains access to food, protection, transport or support.
An example here would be the relationship between barnacles and whales. Here, only the barnacles gain a benefit, where they are provided with free transport and gain access to nutrient rich waters. Some scientists believe that barnacle larvae have adapted their breeding period to match that of the whales, in order to increase the chances of finding a host.
In the symbiotic relationship of parasitism, derived from Latin meaning “one who eats at the table of another”, a parasitic organism lives off a host organism at the host’s expense. There are various types of parasitic relationship; parasites can live internally or externally and may or may not be completely dependent on their host.
Mistletoe is an example of a parasitic organism, developing specialised roots that penetrate a host plant to tap into its water and nutrient sources. While a tree can survive a small number of mistletoe plants, it will become weakened and may lose some of its branches. A larger infestation however, can lead to the host’s death, killing both tree and mistletoe. Apple, poplar and lime trees are the most susceptible to infestations, where mistletoe seeds are deposited on their branches through bird droppings.
Competition symbiosis covers the battle between organisms. It is different to the other symbiotic types as both the same (intraspecific competition) or different species (interspecific competition) can compete for the same resources. There are three main types of competition relationships: interference competition (direct competition), exploitative competition (indirect competition) and apparent competition (when two species are negatively impacted by a shared predator).
Black walnut trees exhibit interference competition, releasing a chemical called jugalone into the soil through fallen leaves, inhibiting competitor plants from growing nearby. In ocean reefs, coral and algae exhibit exploitative competition by competing for sunlight and space. If too much fast-growing algae is present, it can be detrimental to the slower growing coral. Apparent competition is demonstrated, for example, when the population of skinks (a small lizard similar to a gecko) decreases as a result of increased rabbit population. Both are preyed upon by ferrets; when the rabbit population increases, so does that of the ferret, which causes a decline in both prey species.
The modern-day natural environment we live in is very different to the one our grandparents knew. It is changing at an increasingly rapid pace. And from the air we breathe to the places where we live, it can also affect our physical and mental health over time. As the human population grows, so urbanisation expands and global warming rises, understanding the complex relationship between our health and our environment is important to the future of our well-being.
With the increase in human industrialisation over the last 200 years, the quality of our air and water supply has drastically declined. Chemicals such as carbon monoxide and nitrogen dioxide concentrations have increased, with fine particulate matter causing the most serious health issues and premature mortality. Air pollution alone is responsible for 2 million deaths in China per year.
In developed countries, water contamination from urban runoff, industrial waste, pesticides and eutrophication can lead to health issues such as kidney disease and cancer. In developing countries, limited infrastructure and poor sanitation often leads to contaminated water supplies, containing harmful bacteria and diseases which when consumed and contracted cause illnesses such as cholera, diarrhoea and dysentery.
Climate change to our environment exacerbates the effects of air pollution through changes in weather patterns and increased heat levels. It can also encourage the spread of insects that carry infectious diseases, such as ticks and mosquitoes, create storm surges from increased precipitation, leading to industrial overflow and increase draughts, leading to agricultural failure and malnutrition in poorer countries.
The loss of green spaces in urban areas can lead to heat islands and the reduction of opportunities for recreational activity. Poor housing conditions or overcrowding can increase the spread of diseases; COVID-19 for example, is more prevalent in urban areas, where 90% of all reported cases have taken place. Urban spaces also see a higher, disproportionate number of injuries or fatalities compared to rural areas, while increases in noise pollution such as that from construction and traffic can lead to poor sleep, hypertension and heart disease.
The urbanisation of environment also provides opportunities for education, healthcare and employment opportunities, leading to better prospects and well-being. It has also, however, been associated with increased levels of mental health decline, due to social isolation and lack of green spaces. Having a close-knit community and a strong social network is important to our well-being and can help improve our mental health and enhance our recovery from illnesses.
Addressing environmental issues such as pollution, climate change and inadequate infrastructure will help to develop a healthier population. Countries such as Singapore and Denmark are already leading the way forward in urban environments with integrated urban greenery, sustainable development, bicycle infrastructures and community engagements spaces. Whether the rest of the World can follow them as well in time remains to be seen.
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