The mammals are the class of vertebrate animals characterized by the presence of mammary glands, which in females produce milk for the nourishment of young; the presence of hair or fur; and endothermic or "warm-blooded" bodies. The brain regulates endothermic and circulatory systems, including a four-chambered heart. Mammals encompass some 5,500 species (including Humans), distributed in about 1,200 genera, 152 families and up to 46 orders, though this varies with the classification scheme.

Phylogenetically, Mammalia is defined as all descendants of the most recent common ancestor of monotremes (e.g., echidnas and platypuses) and therian mammals (marsupials and placentals).

Mammal anatomy

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Skeletal system

The vast majority of mammals have seven cervical vertebrae (neck bones), including bats, giraffes, whales, and humans. The few exceptions include the manatee and the two-toed sloth, which each have only six cervical vertebrae, and the three-toed sloth with nine cervical vertebrae.

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USDA Agricultural Research Service

Techniques for Managing Cover Crops
Wed, 03 Sep 2008 08:23:00 -0500
Read the magazine story to find out more. Rolling machines designed by ARS researchers may be the fastest way for farmers to prepare fields with cover crops for planting. Click the image for more information about it. Researchers roll out the rye to reign in weeds   Conservation tillage has immediate benefits   Lower CO2 loss in fall tillage Managing Cover Crops with Rolling and Crimping Techniques By Laura McGinnis September 3, 2008 Rolling hay, rye and other cover crops could be the fastest way for some farmers to prepare their fields for planting. That's thanks to rolling machines--developed by Agricultural Research Service (ARS) scientists--that can quickly flatten mature, high-biomass cover crops such as rye. Each roller consists of a long cylinder adorned with a series of thick, blunt, steel crimping bars, each about one-quarter-inch thick. As a standard tractor pulls the roller over the field, pressure from the bars flattens and damages the cover crop without cutting or uprooting it. Within three weeks, the rolled cover crop dries out, forming a mat of dead biomass into which farmers can plant cash crops. Since 2001, ARS has been conducting research to find the best crimping roller design for conditions in the southeastern United States, and the benefits from this research are gaining recognition. ARS scientists Ted Kornecki and Randy Raper and their colleagues at the agency's National Soil Dynamics Laboratory (NSDL) in Auburn, Ala., compared three different roller designs. The first roller has a traditional design with long, straight, horizontal bars. The second has diagonal bars that curve around the roller. The third has a smooth drum attached to a crimping bar that mashes the rye as the machine moves forward. NSDL scientists, who developed the curved-bar and crimping roller designs, found that all three models killed enough rye--90 percent or more--to enable farmers to begin planting cash crops in the field within three weeks. The crimping-bar roller yielded the best results. The scientists also found that the curved-bar and the crimping rollers provided smoother rides than the traditional straight-bar roller. Future studies will help scientists maximize the efficiency and comfort of these machines. The one-pass process saves money, reduces soil erosion and runoff, helps control weeds, conserves water in the soil and decreases or eliminates the need for herbicides. Read more about the research in the September 2008 issue of Agricultural Research magazine. ARS is a scientific research agency of the U.S. Department of Agriculture.
ARS Researchers Search for Casuarina Biological Control Agents
Tue, 02 Sep 2008 09:48:00 -0500
Read the magazine story to find out more. Invasive Australian Pine, Casuarina equisetifolia. Photo courtesy of Forest & Kim Starr, U.S. Geological Survey, Bugwood.org. Foreign herbivores may be key to curbing invasive weeds   Alternate methods of whitefly control   Groundbreaking for new biological control lab ARS Researchers Search for Casuarina Biological Control Agents By Alfredo Flores September 2 , 2008 Australia's Outback and remote coastlines are home to insects that could be key biocontrols for a highly invasive weed threatening coastal areas of the United States, according to Agricultural Research Service (ARS) scientists and cooperators. ARS entomologist Greg Wheeler and his ARS and university colleagues are touring the Outback and Australia's coastal areas in search of biological control agents for the highly invasive Casuarina species commonly called Australian pine. This weed is infiltrating U.S. coastal areas, especially in south Florida, the Virgin Islands, Puerto Rico and Hawaii. Known for its rapid growth and dense coverage, Australian pine inhibits the growth of native plants. The Australian pine problem includes three Casuarina species--C. equisetifolia (referred to in Australia as “coastal she-oak”), C. glauca (“swamp she-oak,” and arguably as big or a bigger problem than C. equisetifolia) and C. cunninghamiana (“river she-oak”). In the past few years, the Australian members of the team--Matthew Purcell and Bradley Brown, researchers at the ARS Australian Biological Control Laboratory in Indooroopilly, Queensland, and Gary Taylor from the University of Adelaide, Australia--conducted five separate trips throughout Australia. Purcell, Brown, Taylor and John Gaskin, research leader of the ARS Pest Management Research Unit in Sidney, Mont., collectively comprise a Casuarina research team. Wheeler served as the lead scientist for the project, coordinating the funding, surveys and plant-DNA testing. From a bounty of some 300 wasps, weevils, stem-borers, sap-suckers, seed-eaters and more, the scientists have narrowed the field of potential control agents to about 12 candidates. Not only do these top candidates attack C. equisetifolia, but many also attack C. glauca and C. cunninghamiana. Among the top finds were the seed-feeding wasp Bootanelleus orientalis, which is host-specific to Australian pine, and the defoliator moth Zauclophora pelodes. These insects are still undergoing testing by Purcell and colleagues in Australia to determine their suitability for use as biological control agents in the United States. Insects that decrease Casuarina reproduction and spread are being given the most attention. Read more about the research in the September 2008 issue of Agricultural Research magazine. ARS is a scientific research agency of the U.S. Department of Agriculture.
Diptera Database Developed
Fri, 29 Aug 2008 08:23:00 -0500
Mexican fruit flies are just one of the species in the order Diptera, one of the four largest groups of living organisms on Earth. Click the image for more information about it. Fruit fly diversity is in the details   Fruit fly study provides insight into bee immune system   Virulent hessian flies renew attack on U.S. wheat Database Documents Names for More Than 150,000 Diptera Species By Ann Perry August 29, 2008 Distinguishing between insect pests and partners starts with an ironclad identification. So Agricultural Research Service (ARS) entomologist Chris Thompson headed up efforts to accurately identify and name almost 157,000 flies, gnats, maggots, midges, mosquitoes and related species in the order Diptera. Diptera is one of the four largest groups of living organisms on Earth, and its members are critical components in virtually all non-marine ecosystems. Carl Linnaeus, who devised the scientific classification system still in use today, compiled the first index of Diptera species names in 1758. But even though an average of 800 new Diptera names are proposed every year, the nomenclature has not been comprehensively updated since 1805. Thompson works at the ARS Systematic Entomology Laboratory in Washington, D.C. For this research, he partnered with Neal Evenhuis, an entomologist at the Bishop Museum in Honolulu, Hawaii; Thomas Pape, an entomologist at the Natural History Museum of Denmark; and Adrian Pont, an entomologist at the Oxford University Museum of Natural History in Oxford, England. The group assembled the tenth edition of the Biosystematic Database of World Diptera (BDWD). This massive index contains nomenclature data for 156,599 living and extinct Diptera species in 154 families and 11,671 genera—around 10 percent of the known biodiversity in the world today. The BDWD, which is available at www.diptera.org, has two components. The Nomenclator allows users to check names, confirm species status, and obtain information about type, family classification and sources for all names in the collection. The Species database is being designed to answer queries about different species, including their distribution, biological associates and economic importance. The BDWD provides a framework for organizing and integrating current and future data that is accessible by researchers around the globe. Scientists can obtain a wealth of information that will help them fine-tune Diptera’s evolutionary tree and track the migration, increase and decline of economically-important Diptera species worldwide. The team presented their research at the 20th International Congress of Zoology in Paris, France, in August. ARS is a scientific research agency of the U.S. Department of Agriculture.

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