Ecosystems have developed on Earth, including a wide variety of animals, plants, protists, fungi, bacteria, and archaea. Life on Earth is diverse, and we, Homo sapiens, are the result of billions of years of biological evolution, leaving traces of that change in the form of rocks and fossils. The distant ancestors of all modern life evolved in the ocean when the continents began to form, some of which produced the oxygen that filled the atmosphere. More than a billion years ago, the remains of microscopic marine organisms began to form the first oil deposits. As life evolved and erosion from the expanding continental surface washed minerals into the water, the chemical composition of the ocean changed. The mineral elements became concentrated, and marine animals used them to adapt to the changing environment and form the first skeletons. More than 350 million years ago, as early amphibians crawled onto the continental surface where the first forests lived, their bones adapted to support their weight, leaving behind the earliest coal deposits.
Over the past hundreds of millions of years, bones have evolved to help organisms defy gravity. Nearly all terrestrial vertebrates (land animals with a backbone) use their limbs to support their weight from below, keeping their spine roughly parallel to the earth. They started out on four legs, but developed senses to better navigate challenging environments. Eventually, some animals evolved to walk bipedally, balancing on two legs. Bipedal walking is not uncommon in the animal kingdom, but it requires a better sense of balance and muscle control. Humans evolved a unique bipedal gait, balancing on two legs while keeping the spine vertical, and bones continued to evolve to support our weight against gravity in a particularly unstable position. Many Homo sapiens bones, joints, and muscles continue to evolve to accommodate our changed orientation and postural habits influenced by modern demands.
We humans have a huge brain housed inside a skull that sits atop a vertical spine. This amazing brain is the organ we use to reason, communicate, sense our environment, explore nature, and understand evolution over time. Our brain allows us to perceive space and time and classify changes as they occur. Amazingly, we have collected fragments of 4.5 billion years of Earth history that allow us to fully understand Earth’s evolution. We know how the Earth formed, the oceans evolved, the continents grew, generations of plankton died and oil formed, animals evolved to create fossilized bones, and forests evolved to form coal seams. Later, primates evolved in the forest canopy and developed senses that they use to understand their changing environment. Our understanding of Earth’s history is never complete. There is too much lost and found evidence, too much space and time to sift through. We have discovered that we, Homo sapiens, are unique in our upright posture, our imagination, and our ability to create with the resources of the world we live in. We have learned that everything on Earth is a resource and have developed products using plants, animals, fungi, protists, bacteria, archaea, minerals, rocks and fossils.
Homo sapiens is only one species on a vast tree of life that gave rise to many organisms, each unique in its own way, and each part of the evolving ecosystem of the Earth. Relatively recently in the history of the Earth, some Homo sapiens began to believe that they could dominate nature, becoming the first organisms to try to separate themselves from the environment. They pretended that we were separate from the environment in which we evolved and on which we still depend. Our attempts to dominate nature have only led us to realize that our understanding of the complexity of the environment is still limited compared to the vastness of Earth’s time. In reality, we have no control over the planetary environment, but we influence it and, conversely, the environment influences us. With our growing population and use of the Earth’s resources, we are unconsciously or consciously directing trends of environmental change, affecting the entire ecosystem.
Homo sapiens’ relationship with the Earth is unique because we are increasingly aware of how we affect and are affected by the Earth’s environment. We have changed the chemistry of the atmosphere, the temperature of the oceans, the reflectivity of the continents, and the diversity of ecosystems. We have made choices that have led to environmental destruction and destabilization, but we can also choose to interact in ways that lead to stability and balance for ourselves and for other species that are part of the Earth’s ecosystem. Our present and future choices require us to resume our role within the ecosystem, to see ourselves as part of the environment, and to choose to be part of nature. We are perhaps the first organisms on Earth that have become aware of our place in the Tree of Life and in the history of the Earth. For the first time in Earth’s history, a species has the opportunity to consciously shape the future of the Earth with the awareness that we are part of and dependent on the Earth’s ever-changing environment.
One environmentally sustainable decision each of us can make is to avoid single-use plastics. Since 2011, July has been “Plastic Free” month.This is a challenge to refuse to use single-use plastic for a month. I hope that this will change our consumption habits for life. Plastic production has a negative impact on the ecosystem and our bodies in every way, and we should only use it when necessary. To celebrate Plastic Free July, I created a web page. Earth Education Website “Sustainable Choices”It provides links to websites that can help consumers make environmentally conscious decisions and offers information on choosing sustainable materials. Avoid plastic because it is made from crude oil and is literally made from the remains of past organisms.While we dig into the past to better understand how the Earth has changed, removing the remnants of past ecosystems and turning them into fuel, bags, toys, dishes, food wrap and water bottles is not the best use of the Earth’s resources. Homo sapiens is blessed with resources, but we need to be more careful about which resources we use. There are many other options that can have a positive impact on our health and environmental sustainability.and establish a conscious decision to invest in the environmental stability of the Earth and support the evolution of the planet’s ecosystem.
