A third of the genera occur as parasites of vertebrates about 35 nematode species occur in humans. The many parasitic forms include pathogens in most plants and animals. The roughly 2,271 genera are placed in 256 families. They have been shown to play crucial roles in polar ecosystems. Their numerical dominance, often exceeding a million individuals per square meter and accounting for about 80% of all individual animals on earth, their diversity of lifecycles, and their presence at various trophic levels point to an important role in many ecosystems. In total, 4.4 × 10 20 nematodes inhabit the Earth's topsoil, or approximately 60 billion for each human, with the highest densities observed in tundra and boreal forests. They represent 90% of all animals on the ocean floor. They are found in every part of the earth's lithosphere, even at great depths, 0.9–3.6 km (3,000–12,000 ft) below the surface of the Earth in gold mines in South Africa. They are ubiquitous in freshwater, marine, and terrestrial environments, where they often outnumber other animals in both individual and species counts, and are found in locations as diverse as mountains, deserts, and oceanic trenches. Nematodes have successfully adapted to nearly every ecosystem: from marine (salt) to fresh water, soils, from the polar regions to the tropics, as well as the highest to the lowest of elevations (including mountains). Although the highest estimates (up to 100 million species) have since been deprecated, estimates supported by rarefaction curves, together with the use of DNA barcoding and the increasing acknowledgment of widespread cryptic species among nematodes, have placed the figure closer to 1 million species. A subsequent publication challenged this claim, estimating the figure to be at least 40,000 species. A widely referenced article published in 1993 estimated there may be over 1 million species of nematode. Estimates of the total number of extant species are subject to even greater variation. A 2013 survey of animal biodiversity published in the mega journal Zootaxa puts this figure at over 25,000. Consequently, estimates of the number of nematode species described to date vary by author and may change rapidly over time. Nematode species can be difficult to distinguish from one another. Like tardigrades, they have a reduced number of Hox genes, but their sister phylum Nematomorpha has kept the ancestral protostome Hox genotype, which shows that the reduction has occurred within the nematode phylum. Taxonomically, they are classified along with arthropods, tardigrades and other moulting animals in the clade Ecdysozoa, and unlike flatworms, have tubular digestive systems with openings at both ends. They are a diverse animal phylum inhabiting a broad range of environments. We designed each to last the life of your car, while providing you with improved performance for the entire time.The nematodes ( / ˈ n ɛ m ə t oʊ d z/ NEM-ə-tohdz or NEEM- Greek: Νηματώδη Latin: Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant- parasitic nematodes also known as eelworms. There are reasons why Ford didn't make the stock K-member lighter it weighs what it does because it provides optimum strength and durability.
The potential weight reduction of 57 lb is still a far cry short of the often claimed 75-100 lb reduction. Sure, there are companies that make lighter-weight K-members, dropping as much as an additional 18 lb. While the weights of the individual parts do vary slightly, the differences are quite small, with the overall weight reduction being just a very few pounds shy of this Fox example. What about the weights for an SN95 Mustang? This particular combination of MM parts for a Fox chassis Mustang provides a weight reduction of 38.8 lb.
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