Introduction
Fossil records indicate life has existed on this planet for at least 3.8 billion years. Most species that have ever existed are now extinct, yet the diversity of life on Earth is still so tremendous and complex scientists estimate there are 10-100 million species yet to be documented. Those that have been documented, have been categorized it into three domains, six kingdoms, twenty-nine phyla, and countless more subdivisions. Seemingly in spite of this diversity, a common ancestry unites all life on Earth. From mosses on trees to bonobos in Zaire, all life shares special characteristics that bind us together. The most substantial evidence of this relatedness has come from careful examination of specimens from the fossil record, as well as the sequencing of genomes from many organisms.
Humans are heavily reliant on the diversity of life that occurs on Earth; from the microbes in soil, to oxygen producing plants and pollinating insects, to the animals we eat and wear and to the trees we cut down, reorganize and live in, human existence – as we know it – is completely dependent upon a tremendous diversity of life on this planet. We are going to explore the domains and kingdoms into which life is categorized in hopes of better understanding the unity and diversity of life on Earth.
Domains: Archea and Bacteria
Characteristics of these domains
Perhaps the most readily noticeable characteristic of archaea and bacteria is their size. These domains are comprised of the smallest, self-sustaining forms of life on the planet. Bacteria and archaea are prokaryotic, thus lack a nuclear envelope and membrane-bound organelles. They also present with circular chromosomes, sometimes referred to as “ring-DNA”. Many archaea are known a...
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...ironment affects the organism. When organisms disappear from environments and ecosystems, other species that have come to rely on them through millions of years of coevolution are almost invariably impacted for the worse.
Our actions as humans have setoff what scientists recognize as the sixth mass extinction event. At a time when the global, human population is as high it has ever been, and is still growing rapidly, more and more pressure is being applied to ecosystems and habitats of all types, all over the globe. Though this planet is finite, and thus cannot be “saved”, it is largely in human hands how long we and the remaining species of life exist. Perhaps we, as a species, will awaken to plight with which we are burdening our progeny and correct our course. Alternatively, we may continue on, helping nature select against beings of “higher” intelligence.
Biosphere The Realm Of Life. Authors: Robert A. Wallace, Jack L.King , Gerald P.Sanders – 1998
In conclusion, despite Archaea’s close relationship to both bacteria and eukaryotes there is sufficient evidence for this group of organisms to be classified as its own domain, due to its unique characteristics in structure and extremophilic nature.
- - -. The Rise of Life on Earth. New York: New Directions, 1991. Print.
As the decades pass, technological advances have enabled researchers, entrepenures and pondering minds the ability to discover more and more about every aspect of our very existence. Over the past three decades the evolutionary tree of life has been expanded at least seven times over. Major advances have been made in the area of evolution to open the eyes of many to the extensive history of the earth. For the very first time, we have tangible knowledge that life evolved and grew to become a flourishing success during the young ages of the Earth. By 3.5 million years ago life was already well advanced. Before this breakthrough no one could have thought that life occurred so amazingly early, that Earth was inhabited by a huge array of tiny life forms through t the first four-fifths of it’s existence, and no one deduced that evolution itself evolved over geologic time.
diverse array of biological life forms and biological materials essential for the survival of all
Environmental activist, David Suzuki, explains how the progression that allowed Homo sapiens to advance into a “super species” may be the primary factor to what ends the wellbeing of our future. In his excerpt from “Rediscovering Our Place in Nature”, Suzuki goes into detail about how the components of life on Earth should not be compromised for the desires of a portion of the people who live there.
The human race has a seemingly impossible challenge before them. While many focus on huge social issues such as terrorism and world hunger, which are completely valid and important issues, many have forgotten about the state of humanity’s neighbors within our very planet. Earth is in the midst of its sixth great extinction, keyed as the Holocene Extinction after the current epoch the planet is in. The Holocene Extinction, starting between 9,000 and 13,000 years ago, is the most recent since the Cretaceous-Tertiary mass extinction, during which the dinosaurs were wiped out (Heymann, Chibante and Brooks). Such knowledge of our current ongoing mass extinction event is not well known among the common populace. The simple fact is that the human
Another factor that is necessary for life evolving is a Star's size. Our Sun is a very ordinary star in terms of it size and temperature. Statistics show that there are billions of stars like the sun in our galaxy alone. ( Henbest & Couper, 1989, paragraph 5 ) Life evolving in one of these star systems may have developed in the same way humans have. Philosophers have argued for centures about how to define life. " If we study living things on the Earth, we find that there are some very basic characteristics that will guide us when we consider life elsewhere in the Universe." ( Henbest & Couper, 1989, paragraph 7 ) Life on Earth shows immense diversity. From organisms such as sea slugs to the human being. All life on Earth are made up of the same basic units, cells. Each cell is built up from chains of carbon, the most importan...
THESIS: Life on earth has been considered by some as a purposeful interaction tending toward ecological stability. However, when the scientific community led by James Lovelock tried to match this concept with science, it was (and continues to be) a dilemma.
There as not only been a decreased number of species from this environmental crisis; but even in parts of the globe were exotic living beings used to flourish, now are at an all-time low when it comes to how many of them are left of this Earth. “Today we’re living through the sixth great extinction, sometimes known as the Holocene extinction event.” (Whitty, 2015) In future generations, those kids would be lucky if they even get to see a rhino or elephant in their life because of how much these animals are exploited and slaughtered for nothing other than blind greed. “Of the 40,168 species that the 10,000 scientists in the World Conservation Union have assessed, one in four mammals, one in eight birds, one in three amphibians, on in three conifers and other gymnosperms are at risk of extinction.” (Whitty, 2015) In the latest centuries recorded extinctions, the current rate is one hundred times the background rate. It’s shocking that on average somewhere between 2.7 and 270 species are eliminated from existence every day. If we remain on the road of frivolous destruction, half of all the worlds’ plant and animal species will cease to exist. Keeping in mind that the circle of life does exist and animals and plants will eventually die just like all of us one day; but humans continually take advantage of natural resources and other living beings. The only way to save Earth’s membrane is to salvage what is left of its beauty and assemble its broken pieces back together. Surprisingly, not all hope in humanity is lost. The strive to rewilder North America is one of the many positive steps that need to be taken. Starting with reconnecting what remains of wilderness parks, sanctuaries, and national parks. In addition to those actions, North America must also rekindle the four broad “megalinkages” which include “the Rocky
Humans are destructive. Not a lot of us think about how what we do affects the world around us. We almost act like we are the only ones on this planet. We go around polluting and destroying our world with no regard for our actions. The things that live out in the wild are paying the price for it. Every day that passes there is another animal or plant that is placed on an endangered list. This is happening at an alarming rate. Because of man’s desire to expand and conquer their surroundings, there are animals and plants that are on the brink of extinction that will not be around for our kids and future generations to enjoy if something is not done about it now. This problem has been going on for hundreds of years. There are animals and plants that can only been seen in paintings or early photography. It is because of our early ancestors that we have this problem today and we have to do more to prevent more animals and plants from disappearing forever.
Through millions of years of evolution, well-balanced habitats have co-evolved to provide for the wide variety of species and their needs. Trees have adapted to weeds, weeds have adapted to the predation from herbivores, and so on up the food chain. Similar scenarios are seen throughout the world. Through the process of natural selection, specific species or broad species families will go extinct. However, these occurrences have largely been due to the natural flow and evolution of time. It wasn’t until recently that dominant species, such as humans, have taken the course of nature into their own hands.
There are many different forms of life. These differences have both advantages and disadvantages to them. These differences vary in
In The Diversity of Life, Edward O. Wilson reflects on how the living world became diverse and how humans are destroying that diversity. In the book’s preface, Wilson defines biodiversity as “the totality of inherited variation in all organisms in a selected area” (Wilson ix). He adds that modern technology will allow for us to find many new species that were previously unknown to be in existence.
Biodiversity refers to wide diversity found in the living components of the earth which refers to the numerous varieties of flora and fauna including those of microorganisms too. The interaction of biotic and abiotic components of the ecosystem is very important aspect of life on earth. Biodiversity helps us to understand the variations among species and also how life originated on earth. Its study helps us to understand the inter-relationship between various forms of life and their adaptation to different conditions.