Amphibian means “double life” referring to the fact that most adult amphibians live on land while embryos need water to survive. Some amphibians have been around since the Jurassic age; however the numbers of these long alive animals are declining around the world (Amphibia). As of 2010, 32% of the world’s 6600 amphibian species were threatened with extinction (Hayes, Falso, Gallipeau, Stice 2010). There is no single cause of the amphibian decline, but it seems that habitat loss, like deforestation, is the main reason along with human impact in terms of urbanization, forest fragmentation, predation, human exploitation, pathogens and climate change (Hayes, Falso, Gallipeau, Stice 2010). The climate is decreasing amphibians because of the increase of temperature, less rainfall, higher UV radiation levels and increases in pesticides. The declining population rate is also a factor; there is more death and reduced birth rates among amphibians. The amphibian population decline was considered a global phenomenon in the early 1990s and some experts consider this decline the Earth’s sixth mass extinction (Hayes, Falso, Gallipeau, Stice 2010).
One way to gather information about the amphibian decrease was done by the Global Amphibian Assessment or GAA. The GAA was the first-ever global assessment the amphibian conservation status and takes into account the 5,743 known species in the world, according to the GAA (AmphibiaTree). The results of the GAA are posted for public knowledge on the Amphibian Specialty Group Website (Animal Specialty Group). There is an assessment on the amphibian decline, including the Red List threat, the regions and ranges of certain amphibians, and general ecology information (AmphibiaTree). The GAA has stated t...
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The Sixth Extinction: An Unnatural History details the continued loss of biodiversity that has occurred since the rise of mankind. Elizabeth Kolbert claims that we are now in the midst of a sixth mass extinction, and that, if precautionary measures are not taken, the loss of biodiversity would be catastrophic. Chapter one begins by describing the golden frogs in the town of El Valle de Antón, and how they were beginning to disappear. The frogs disappeared due to a fungus called Batrachochytrium dendrobatidis. This fungus has spread around the world at a lightning-quick rate, killing all sorts of amphibious organisms at an unnatural rate. The cause of the rapid spreading of the fungus has been theorized to be due to humans inadvertently spreading
The eradication of species numbers average at a toll close to one hundred percent of earths total living creatures. “It is the Earth's most severe known extinction event, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct” (Sahney, and Benton 759). Not only where marine and terrestrial species effected but this catastrophic event is the only recogni...
When researching the population decline of amphibians as a global issue, it is evident that there have been drastic changes in the past 30 years. Mike Lannoo from the U.S. Declining Amphibian Task Force says that there have been significant losses in amphibian populations for an extensive period of time (No Single Reason, 1999). Stuart et al. (2004) stated that according to scientists at the International Union for Conservation of Nature (IUCN), at least 427 species, roughly 7.4%, are at a dangerously high risk of extinction (Kaylor, 2006). The problem of amphibian decline cannot be linked directly to one single cause (No Single Reason, 1999). Instead, scientists have related the decline to disease, habitat loss, changes in climate, and pollution (Hayes, Falso, Gallipeau, Stice, 2010; Brooks et al., 2002; Dunson et al., 1992). It is concluded that many of these factors are related to and possibly caused by human interaction (McCallum, 2007). The declines could be caused by pathogens, climate change, or wildlife toxicology, says Dr. Ashley Mattoon from the Worldwatch Institute (Kirby, 2000).
Long-term survival of a species depends on its ability to adapt to changing environmental conditions (Murphy, 1994). Genetic diversity within a species, which has taken 3.5 billion years to evolve, makes adaptations to these changing environments possible. Unfortunately, the rate of extinction of genetically diverse organisms is rapidly increasing, thus reducing this needed biodiversity, largely due to the human impacts of development and expansion. What was an average of one extinction per year before is now one extinction per hour and extinct species numbers are expected to reach approximately one million by the year 2000 (WWW site, Bio 65). As a result governmental and societal action must be taken immediately!
With global warming on the increase and species habitats on the decrease, the chances for various ecosystems to adapt naturally are diminishing. Many studies have pointed out that the rates of extinction of animal and plant species and the temperature changes around the world since the industrial revolution have been significantly different to normal expectations.
Lawrence, Timothy, and Walter S. Sheppard. "Neonicotinoid Pesticides and Honey Bees." Cru.cahe.wsu.edu. Washington State University, Nov. 2013. Web.
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Frogs are amphibians in the order Anura. The order Anura is broken down into 22 different families of frogs and toads. Although they belong to the same order, frogs and toads are different in a lot of ways. Some of the more distinct differences are their skin and where they live. Frogs usually have smooth moist skin and toads usually have dry watery looking skin. Frogs spend most of their lives in or near water and toads spend more time on land. Amphibian means "double life." Frogs and toads each have two parts to their lives: when they live on water and when they live land. A frog's life starts in the water when it is hatched from an egg as a tadpole. A tadpole looks very different from an adult frog. A tadpole has a tail, no limbs, and breathes through gills. After a while the tadpole goes through metamorphosis. During the change the frog grows limbs, the tail disappears, it uses lungs to breathe, and it doesn't have to live in water anymore. As a tadpole, the frog feeds mostly on vegetation. The tadpoles have a small rasping mouth suited especially for scraping algea from the bottom of ponds. Depending on the species, it can take a few weeks to a year or more for the tadpoles to become fully grown. Not all frogs hatch as tadpoles. Some species of frogs hatch as froglets. Froglets look just like adult frogs but are a lot smaller. Froglets don't go through a metamophosis. Most species that hatch as froglets are found in dry places. Frogs who live in dry places where rains are seasonal have to grow up quickly because a tadpole will die if their temporary pond dries up. Adult frogs can live in water or on land, but it always needs to be near water so its respiratory organs don't dry out.
Thousands of species have become extinct over the last four decades as a result of changes in land use and as a result of global warming. Whether or not the millions of species can adapt and evolve to climate changes is debatable. As this brief overview will report, the human species is not adapting well to the changes. It must be remembered that increases in the levels of carbon dioxide are certainly responsible for the risk many species face, but so is the way land is used, e.g., rain forest destruction. There is a feedback loop wherein plant life and the climate are interdependent. Each affects the other. When forests are cut down, temperatures in that area will rise. Rising temperatures cause other plant life requiring cooler temperatures To die off.
Since the 1980’s scientists have noted the decline of many frog species. People do not know for certain what has caused these declines. A possible factor is pollution, disease, habitat destruction, and acid rain. Another factor may be the thinning of the earth’s protective ozone layer, which allows more harmful ultraviolet radiation from the sun to reach the earth. Because frogs have thin, moist skin and an aquatic tadpole stage, they are easily affected by pollution and changes in the environment.
As time has progressed, there has always been an overarching need for high amounts of crop production throughout the world. With the rapid rate of population growth, the need for crops and other sources of nutrients is only increasing. In order to meet these high demands and increase yields, farmers and other agriculturalists have started implementing the use of pesticides. These chemical mixtures are being used in order to prevent, destroy, repel or mitigate any pests from destroying growing crops. However, using pesticides on crops can create massive amounts of pollution, negatively affect an individual’s health, and can spark biodiversity loss within an ecosystem. According to Michael C.R. Alavanja, “Over 1 billion pounds of pesticides are used within the United States (US) each year and approximately 5.6 billion pounds are used worldwide”. With all this in mind, it is clear that pesticides should not be made available to farmers and agriculturalists, and should
Reptiles are vertebrate, or backboned animals constituting the class Reptilia and are characterized by a combination of features, none of which alone could separate all reptiles from all other animals.The characteristics of reptiles are numerous, therefore can not be explained in great detail in this report. In no special order, the characteristics of reptiles are: cold-bloodedness; the presence of lungs; direct development, without larval forms as in amphibians; a dry skin with scales but not feathers or hair; an amniote egg; internal fertilization; a three or four-chambered heart; two aortic arches (blood vessels) carrying blood from the heart to the body, unlike mammals and birds that only have one; a metanephric kidney; twelve pairs of cranial nerves; and skeletal features such as limbs with usually five clawed fingers or toes, at least two spinal bones associated with the pelvis, a single ball-and-socket connection at the head-neck joint instead of two, as in advanced amphibians and mammals, and an incomplete or complete partition along the roof of the mouth, separating the food and air passageways so that breathing can continue while food is being chewed. These and other traditional defining characteristics of reptiles have been subjected to considerable modification in recent times. The extinct flying reptiles, called pterosaurs or pterodactyls, are now thought to have been warm-blooded and covered with hair. Also, the dinosaurs are also now considered by many authorities to have been warm-blooded. The earliest known bird, archaeopteryx, is now regarded by many to have been a small dinosaur, despite its covering of feathers The extinct ancestors of the mammals, the therapsids, or mammallike reptiles, are also believed to have been warm-blooded and haired.
In many parts of the world, ecosystems’ temperatures begin to rise and fall to extreme levels making it very difficult for animals and plants to adapt in time to survive. Climate has never been stable here on Earth. Climate is an important environmental influence on ecosystems. Climate changes the impacts of climate change, and affects ecosystems in a variety of ways. For instance, warming could force species to migrate to higher latitudes or higher elevations where temperatures are more conducive to their survival. Similarly, as sea level rises, saltwater intrusion into a freshwater sys...
As urbanization continues to expand amphibian population are on a global decline. In many rural areas, the only wetland available for aquatic reproduction is artificial ponds. While some species are able to persist in such an environment the majority of amphibians are negatively affected. The introduction of non-native species along with habitat degradation affects the successful reproduction of these native amphibians. Therefore, an understanding of the relationship between these species and their habitat is essential for conservation. This research sets out to determine conservation priorities for pond breeding amphibians in the hopes of preserving their existing populations.
Pesticide is a chemical used to prevent, wipe out and control the pest problem in agriculture. The use of pesticides have become a common practice around the world, and used almost everywhere, such as agricultural fields, homes, park and school, and so on. Most pesticides are insecticides, herbicides and fungicides that have distinct purposes. Insecticides are used to control insects; herbicides are used to destroy plants; fungicides are used to prevent molds and mildews. Most commonly pesticides contain highly toxic chemical such as Acid copper chromate (ACC), Acephate and Chlorpyrifos, and so on. One of example of insecticides, Chlorpyrifos, sprays widely on a variety of food and golf courses in order to control pests in a cornfield. However, “Chlorpyrifos can cause cholinesterase inhibition in humans; that is, it can over stimulate the nervous system causing nausea, dizziness, confusion, and at very high exposures (e.g., accidents or major spills), respiratory paralysis and death.” (EPA GOV) In the market has thousands of products are similar as Chlorpyrifos.