Essay On Xenophyophores

Xenophyophores

Deep sea is the largest ecosystem on Earth and it exhibited a large diversity of life forms that appeared to be bizarre and curious to both general and scientific communities. The sediment samples obtained from deep seas were usually containing fecal pellets (released by animals lived in photic zone of ocean), foraminiferan tests, as well as organic matters.

Recently, during the July of 2011, researchers with Scripps Institution of Oceanography at UC San Diego and National Geographic engineers carried out deep sea explorations at the Pacific Ocean chasm, discovered and documented the existence of xenophyophores in Mariana Trench (Giant amoebas, 2012). The xenophyophores found in Mariana Trench, according to Tilford (2011), are

The agglutinated tests formed by the xenophyophores are usually consisted of foreign particles, which included various mineral grains, spicule fragments from the sponges, as well as the radiolarian and foraminiferan tests (Hayward et al., n.d.). As reported by Hayward et al. (n.d.), the ability of xenophyophores to grow into large size (ranging from few mm to 20cm) is largely due to the extensive branching of their granellare and the complicated test construction, although the actual volume of plasma of xenophyophore is very low (less than 5%). The color and shape of xenophyophores varied greatly. The xenophyophores can be grouped into branched, reticulate, platy,as well as many different types of intermediate forms (Offshore directory, n.d.). As reported by Offshore directory (n.d.), it is the local environmental conditions that responsible for the diversity of xenophyophore forms. Besides that, the shape of the xenophyophore tests and its pattern of formation were observed to be varied greatly in order to increase the efficiency of feeding process, for example, some tests function as elaborate food particle traps (Levin & Thomas as cited in Offshore directory, n.d., p.

As reported by Levin and Gooday (1992), the food consumed by xenophyophores mostly consisted of detrital particulates. It was observed that within (or adsorbed into) the tests of xenophyophores, there are abundant fecal material that made up of mineral grains (Levin & Gooday, 1992). As xenophyophores are deep sea benthic detritivores, their feeding behavior was thought to be similar to those of amoebas. Three modes of feeding behaviors has been proposed by scientists, namely: suspension feeding (Tendal, 1972), surface-deposit feeding (Lemche et al. as cited in Levin & Gooday, 1992, p. 99), and particulate trapping within the tests (Levin & Thomas,