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Biodiversity

Human Overpopulation Pollution Biological Diversity in Venezuela

Deisy Pulgar


EavEsdropping on naturE givEs CluEs to BiodivErsity Biology professor Mitch Aide uses his ears to learn about the frogs, birds and insects that are all around him. This scientist at the University of Puerto Rico is trying to track how animal populations are affected by a world that’s under increasing pressure from human activities. Aide says, “We would like to have five, 10, 20 years of data of how populations are changing.” In recent years, Aide and his colleagues have been putting recorders in the field so they can listen around the clock to the species they are studying. For example, they staked out a marsh where someone recently discovered a new species of frog. That is a recording from Sabana Seca. It is a wetland on the north coast of Puerto Rico, and this is where we put the original permanent recording station,” Aide says. The solar-powered station makes a one-minute recording every 10 minutes; 144 recordings a day, every day. It’s a great way to keep an ear out for the newly discovered species as well as a half dozen other amphibians in the area. But there’s a catch. “You can save time in the field, but in the end you have to invest a lot of time in the laboratory listening to these recordings,” Aide says. “It’s torture.” So Aide recruited help from the University of Puerto Rico’s computer scientists. As they report in the journal PeerJ, they’ve developed an automated system, called the Automated Remote Biodiversity Monitoring Network, to go through all those recordings and pick out the sounds of the species they’re studying. “The way it works is that the biologist who knows the calls gives the computer examples,” he says. The computer then looks for a match — kind of like the way the Shazam or SoundHound apps can listen to a song playing on the radio and tell you what it is.

Aide is encouraging field biologists everywhere to use his open-access system on the project’s website to help build up a library of sound-recognition patterns that researchers can share. “Right now, anybody who has an Internet connection can listen and view over a million recordings that we’ve collected from the different projects,” he says. What’s especially appealing about this is he’s gradually building a permanent repository of field recordings. “One of the things I really like about this technology is that each recording is like a museum specimen. Anybody in 10, 15, 20 years can go back with new technology, with new ideas, and listen and analyze those recordings again,” he says. Aide’s project is just one example of computerized sound recognition in biology. Cornell University has another project focused on monitoring the world’s oceans using bioacoustics. “We have networks of recording devices around the world listening for fishes and whales as far north as the Arctic Circle, down to the tropics in the Atlantic and Pacific Oceans,” says Cornell’s Aaron Rice. Rice says that means they are also swamped with recordings. “In our lab group, we have years of data that no mere mortal could ever listen to in a single lifetime,” Rice says. So he, too, is working to automate this process by developing computer programs to sift through all that sound to identify animals and track them as they move through the world’s oceans. Rice says the same idea is also taking hold across the parched lands of Australia. “They have a string of recorders going from north to south across Australia and their goal there is to identify the spread of invasive bird species,” he says.


Biological Diversity

Biological diversity, very simply, refers to all of the different kinds of life on Earth. Also called biodiversity, biological diversity is often used to refer to the total number of different species on Earth. A collection of this biodiversity would include human beings, Bengal tigers, sugar maples, oyster mushrooms, bacteria, and the millions of other living or-

ganisms found on Earth. Conservative estimates of the number of species on Earth range from 5 to7 million but some scientists estimate as many as 30 million! With only about 1.6 to 2 million of these species having been studied (many only at the most basic level) and given a name, much still needs to be learned about the diversity of life on Earth. Loss of this biodiversity means

we would not only lose rich and beautiful ecosystems but we might also lose plants and other organisms that could improve or enrich our lives. Already the tropical forests have provided humankind with food crops we enjoy daily such as tomatoes, peppers, corn, rice, coconut, banana, coffee, cocoa, cassava (tapioca), beans, and sweet potatoes, to name but va few.


Biodiversity Biodiversity is most commonly used to replace the more clearly defined and long established terms, species diversity and species richness. Biologists most often define biodiversity as the “totality of genes, species, and ecosystems of a region” An advantage of this definition is that it seems to describe most circumstances and presents a unified view of the traditional three levels at which biological variety has been identified: • • •

species diversity ecosystem diversity genetic diversity

They study processes such as mutationand gene transfer that drive evolution.


Causes of the loss of

biodiversity The main cause of the loss of biodiversity can be attributed to the influence of human beings on the world’s ecosystem, In fact human beings have deeply altered the environment, and have modified the territory, exploiting the

species directly, for example by fishing and hunting, changing the biogeochemical cycles and transferring species from one area to another of the Planet. The threats to biodiversity can be summarized in the following main points:

1. Alteration and loss of the habitats: the transformation of the natural areas determines not only the loss of the vegetable species, but also a decrease in the animal species associated to them. Refer to “Alteration and loss of the habitats”. 2. Introduction of exotic species and genetically modified organisms; species originating from a particular area, introduced into new natural environments can lead to different forms of imbalance in the ecological equilibrium. Refer to, “Introduction of exotic species and genetically modified organisms”. 3. Pollution: human activity influences the natural environment producing negative, direct or indirect, effects that alter the flow of energy, the chemical and physical constitution of the environment and abundance of the species; 4. Climate change: for example, heating of the Earth’s surface affects biodiversity because it evndangers all the species that adapted to the cold due to the latitude (the Polar species) or the altitude (mountain species). 5. Overexploitation of resources: when the activities connected with capturing and harvesting (hunting, fishing, farming) a renewable natural resource in a particular area is excessively intense, the resource itself may become exhausted, as for example, is the case of sardines, herrings, cod, tuna and many other species that man captures without leaving enough time for the organisms to reproduce.


Biological Diversity

in Venezuela is…

…the diversity of ecosystems

Geographical Regions of Venezuela: • Maritime region: desert landscapes and mangroves make up the 311 islands, keys, and islets bordering the Caribbean and Atlantic Coast • Coastal mountain range: dominated by forests • Maracaibo lowlands in the northwest: remarkably flat with only a gentle slope toward the centre and away from the mountains that border the region; Lago de Maracaibo occupies much of the lowerlying territory • Andes cordillera in the west: characterized by páramo vegetation • central Orinoco plains (llanos): the area slopes gradually away from the highland areas that surround it; elevations in the llanos never exceed 200 meters • Guiana highlands in southeast: One of the oldest land forms in South America and composed of savannahs, gallery forests, palm dominated wetlands; consist primarily of plateau areas scored by swiftly running tributaries of the Orinoco; the most conspicuous topographical feature of the region is the Gran

Paramo de Mèrida

Sabana, a large, deeply eroded high plateau; above the rolling surface of this massive, flat-topped bluffs emerge ( tepuis)¬ the most famous tepui contains Angel Falls (Salto del Angel = 965m), the world’s highest waterfall

Lago de Maracaibo

Los llanos

Isla de margarita


Guacamaya azul

Rana lemur

Tortuga verde

…the diversity between and within species

• 650 vegetation types with 15,000 superior plant species approximately • 332 reptile, 113 amphibian, 1,183 fish (exceeding in number all known in North America), 1,348 bird, 100,000 insect species and 328 mammal species • 23% of the flora is endemic • The spectacular table-mountains - the tepuis - offer unique habitats and are home to many endemic plants and animals, due to their geographical isolation over long periods of time Venezuela is Protecting Biodiversity Venezuela’s National Director of Biological Diversity, Jesús Manzanillo, said yesterday that the country’s strategic conservation plan is paying special attention to endangered species and threatened ecosystems. “This plan is constructed on the basis of a very exhaustive analysis of what should be done in the country and in the world and it takes up precise elements of conservation,” he said.

Salto Angel Delfìn rosado


Human overpopulation Occurs if the number of people in a group exceeds the carrying capacity of the region occupied by the group. The term often refers to the relationship between the human population and its environment, the Earth, or to smaller geographical areas such as countries. Overpopulation can result from an increase in births, a decline in mortality rates an increase in immigration, or an unsustainable biome and depletion of resources. It is possible for very sparsely populated areas to be overpopulated if the area has a meager or non-existent capability to sustain life (e.g. a desert). The human population has been growing continuously since the end of the Black Death, around the year 1400, although the most significant increase has been in the last 50 years, mainly due to medical advancement and increases in agricultural productivity. Although the rate of population growth has been declining since the 1980s, the United Nations has expressed concern on continued excessive population growth in sub-Saharan Africa Causes

The root causes for overpopulation are multifaceted and complex. From a historical perspective, technological revolutions have coincided with population explosions. There have been three major technological revolutions the tool-making revolution, the agricultural revolution, and the industrial revolution all of which allowed humans more access to food, resulting in subsequent population explosions. For example, the use of tools, such as bow and arrow, allowed primitive hunters greater access to high energy foods (e.g. animal meat). Similarly, the transition to farming about 10,000 years ago greatly increased the overall food supply, which was used to support more people. Food production further increased with the industrial revolution as machinery, fertilizers, herbicides, and pesticides were used to increase land under cultivation as well as crop yields. In short, similar to bacteria that multiply in response to increased food supply, humans have increased their population as soon as food became more abundant as a result of technological innovations.


Pollution

The litter problem on the coast

Effects

Human health Adverse air quality can kill many organisms including humans. Ozone pollution can cause respiratory disease, cardiovascular disease, throat inflammation, chest pain, and congestion. Water pollution causes approximately 14,000 deaths per day, mostly due to contamination of drinking water by untreated sewage in developing countries. An estimated 700 million Indians have

Air pollution from a World War II

Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of chemical substances or energy, such as noise, heat or light. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Pollution is often classed as point source ornonpoint source pollution.

no access to a proper toilet, and 1,000 Indian children die of diarrhea every day. Nearly 500 million Chinese lack access to safe drinking water, 656,000 people die prematurely each year in China because of air pollution. In India, air pollution is believed to cause 527,700 fatalities a year. Studies have estimated that the number of people killed annually in the US could be over 50,000.

Overview of main health effects on humans

Environment Pollution has been found to be present widely in the environment. There are a number of effects of this: • Biomagnification describes situations where toxins (such • as heavy metals) may pass through trophic levels, becoming exponentially more concentrated in the process. • Carbon dioxide emissions cause ocean acidification the ongoing decrease in the pH of the Earth’s oceans as CO2 becomes dissolved. • The emission of greenhouse gases leads to global warming which affects ecosystems in many ways. • Invasive spevcies can out compete native species and reduce biodiversity. Invasive plants can

contribute debris and biomolecules (allelopthy) that can alter soil and chemical compositions of an environment, often reducing native species competitiveness. • Nitogen oxides are removed from the air by rain and fertilise land which can change the species composition of ecosystems. • Smog and haze can reduce the amount of sunlight received by plants to carry out photosynthsis and leads to the production of tropospheric which damages plants. • Soil can become infertile and unsuitable for plants. This will affect other organisms in the food web. • Sulfur dioxide and nitrogen oxides can cause acid rain which lowers the pH value of soil.


Nature is prodigal, said Darwin. So much waste. “The face of nature may be compared to a yielding surface, with 10,000 sharp wedges packed closely together and driven inwards by incessant blows, sometimes one wedge being struck, and then another with greater force.” His understanding of the conflict driving nature’s apparent harmony was triggered by reading “An Essay on the Principle of Population” by Robert Malthus. This led him to the concept of natural selection and also to ideas about the evolution of instincts and human psychology.He was young: after South America, his mind was racing. “The principle of population is strife”; “All forms compete against others”; “You can understand the true conditions of life only if you use your imagination to hold on to a sense of the ruthlessness of the natural forces that could waste the bright surface.” This side of his work inspired Freud’s insight into psychic conflict and the origins of human aggression. “The human mind is shaped by its animal past,” said Darwin. Nature’s ruthlessness is ours, too: our bodies, our psyches. Unlike a blackpoll warbler, we can’t fly away when resources are gone. In our time, it seems, Arctic and tropic will change their meanings again. But biodiversity may no longer be part of the equation. Tags: nature

Feeding the world with a mix of science and tradition The biotech industry has long sought legitimacy by claiming that its genetically modified crop technologies are “feeding the world”. However this relentless focus on increasing food production ignores the fact that mass hunger exists alongside a huge food surplus. To really reduce world hunger on a permanent basis, we need to embrace the ideas of food sovereignty, which highlights the politics of food, in terms of resource ownership, market control and decision-making power; and the concept of agroecology, which blends traditional farming knowledge with modern understandings of on-farm ecosystem services. Last month, the World Food Prize was awarded to scientists from Monsanto, Syngenta and other bioengineering companies. Sponsors of the prize (including Monsanto, Syngenta, Cargill, Archer Daniels Midlands, Walmart, and Pepsi) claim that it is “the foremost international award recognising individuals whose achievements have advanced human development by increasing the quan-

tity, quality and availability of food in the world”. The winners spoke glowingly on how biotechnology held “the promise of benefiting all mankind” by producing increased yields through improving resistance to insects and disease, and increasing the capacity to withstand climate extremes. But well-known food movement scholar and activist Eric Holt Gimenez criticised the prize outcome saying it has “become a corporate celebration of self ”.The further development of biotechnologies has been openly endorsed by agricultural exporting countries, including Australia. The newly-released National Food Plan called for the expansion of genetically engineered crops in this country. However, critics say that in over 20 years of commercially-planted, genetically-engineered crops, yield gains have been minimal. In fact, the technology may be causing yields to fall by decreasing biodiversity and contributing to the evolution of superweeds. Herbicide volumes are now rising at 25% per year to cope with these superweeds.


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Horoscopes Aries Even though all continues to go well for you, Aries, your mood may vacillate today. In spite of all the great things in your life, at some time during the day you might feel a little blue. Don’t read too much into it. It’s probably just the result of low biorhythms. Try to distract yourself with physical activity. Go out with some friends and have a good time this evening

Cancer Many projects to complete before a deadline might have you feeling pressured, Cancer, but your determination is likely to drive you to try to get it all done even if it seems impossible. Don’t try to do it all yourself. Ask for a little help. You can accomplish your ends without putting undue pressure on yourself. Try to relax today.

Taurus trying to get too much work done in the course of the day could prove self-defeating, Taurus. Your energy isn’t what it usually is, and you’re probably operating on adrenaline. Consider the situation carefully and list your tasks in order of urgency. The world won’t come to an end if you don’t get them all done by the end of the day. In the evening, watch a movie and order a pizza.

leo You’ve been doing very well, Leo, but today you might feel more focused than ever. The path ahead seems clear and well defined. You’re anticipating the future with motivation. You might be considering a long trip abroad or perhaps going back to school for an advanced degree. This is a good day to research and finalize your plans

Gemini A despondent friend may need some cheering up. Your ability to nurture and listen sympathetically will definitely prove beneficial, Gemini. Take care not to absorb any of this person’s dejection. Your life should continue to go well with professional successes leading to new friendships and goals. Hang on to your enthusiasm and op-

Virgo Some kind of settlement, grant, or bonus that you’ve anticipated for a long time may finally show up, Virgo. This should make your day! You may want to celebrate. A chance to attend a large social gathering might come a notebook and pen by your bed so you can write them down.


Horoscopes Libra today you may put a lot of energy into your romantic relationship, Libra. The astral energy is encouraging you to focus on romance. Give your significant other a special gift to show how much you care, and spend some time alone together. Any romance initiated or advanced today is likely to prove stable and long lasting. Don’t let fear stand in your way. Move ahead.

Capricorn You might host a social event in your home tonight, Capricorn. You may be nervous at first, wondering if all will go well. Your efforts should produce the results you want. You might be introduced to new contacts, which could lead to increased professional opportunities. Take a walk after everyone has gone. Your mind will be going a thousand miles an hour and you will want to clear your head

Scorpio Too much work and the resulting pressure over the past few days may have you feeling too tired to do anything more, Scorpio, although your optimism and enthusiasm are still intact. Don’t be too hard on yourself if you’re dragging by the end of the day. If you take care of yourself, you will soon recharge and be your old self again. In the evening, read a good book.

Aquarius Paperwork, perhaps contracts or other legal documents, might need attention so you can move ahead with your projects, Aquarius. These projects could involve writing or speaking. Your mind is in just the right space to participate in anything involving communication, so doors of opportunity may open for you in this area. Lift your chin and get going. You will be glad you did.

Sagittarius Romance blossoms for you, Sagittarius, perhaps after a long standstill. A new stability and security may settle on love relationships as well as close friendships. Children could be a great source of warmth and pleasure. You might want to channel some of this blossoming positive energy into a creative activity of some kind, which should increase even further your sense of contentment and well-being

Pisces Your financial picture continues to improve. At some point during the day, Pisces, you might have the feeling that you aren’t working hard enough to keep up your current forward motion, and you might worry. This could be a good motivator, but you don’t need to push yourself much harder than you are now. You’re on a roll and it’s likely to continue. Keep moving, but pace yourself.


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