🔎 Foraminifera – Definition and Interpretations

an introduction

The foraminifera It is the protozoa that appeared in Cambrian (Cambrian spanning from -542 ± 0.3 to …). The test (sometimes called, incorrectly, seashells), comprising one or more rooms (or the place where hostel), with one or more perforations (apertures). They have a way to life (Life is the given name 🙂 benthic (in and in sediments) or plankton (in a columnWater (Water is a chemical compound found everywhere on Earth, essential to everyone…), especially in the photoperiod). They generally range in size from 38 µm to 1 mm (some can be over 10 cm). they diet (For human cultural diets see Practice…) Consists of bacteria (Bacteria (Bacteria) are prokaryotic unicellular organisms, characterized by …)algae and mollusk larvae, oysters (Crustaceans (Crustaceans) are arthropods, that is, animals whose bodies …)Various waste.

The story of their discovery

Painting from a book by Dorpigny representing foraminifera

In 1826 Alcide Dessalines d’Orbigny (1802-1857) created the order of the foraminifera in a work entitled Systematic Table of Cephalopods. During his lifetime, Orbigny will describe 1,500 species, most of which are new to Science (Science (Latin science, “knowledge”) is, according to the dictionary…). He was the first to study their lifestyle and environmental requirements. But the unicellular nature of foraminifera was discovered by Félix Dujardin (1801-1860) in 1835. It was thanks to their study that he discovered the protoplasm of unicellular organisms.

Classification Basics

The composition of this test (organic, agglutinating, carbonated, siliceous) is the main classification criterion for foraminifera and is the basis of most classifications, including that of Loeblich and Tappan (1964 and 1988). Foraminifera in Organic Tests They are represented mainly by unicellular fascicles, Allogromiina (suborder). This suborder is still poorly known, since lost in fossil assemblages, it has been little studied by microbiologists. However, the Gooday Group in Southampton (UK) is currently trying to catch up, everything (All is understood as all that exists most often as the world or …) At least when you acknowledge them. Foraminifera in Clustered tests Characterized by contamination of grains taken from sediments (cf. Gudrina sp. , foraminifera in the lower left on the proposed tablet). Grain selection can occur in some species (eg Saccammina micaceus, which only offers mica grains). Two types of foraminifera Carbonate Tests can be distinguished. porcelain has a side white (White is the color of an object heated to about 5000°C (see…) Opaque, while hyaline is transparent and glassy. Finally, foraminifera rock tests Extremely rare. The second classification criterion is the design of dressing rooms. Thus, we can distinguish several main types of tests:

• One-eye tests
• Multiple eye exams:
  • Sequential tests, the boxes are organized into a series (eg Gudrina s) ;
  • Spiral tests (eg snails; the other three examples are on the board);
  • disk tests
  • Milliform tests. The lodges are formed successively and individually in several planes;
  • complex tests.

The third criterion is the decoration of the test. The test may be smooth, but often has growths (ribs, spine, suture bridges, etc.) and depressions. Finally, the fourth criterion is the shape and location of the main opening. Thus, the opening is sometimes associated with additional elements (teeth, lips, plates, etc.) and / or the end of the neck.

microfossils (Microfossils are tiny fossils, the study of which requires resources…) Marine sediments containing radioactive globules, spongy nets (small spines), planktonic foraminifera (small white shells) and benthic foraminifera (large white crust in the center of the image, plus small yellow shells made up of lumpy grains of sand). The Diameter (In a circle or sphere, the diameter is a line segment passing through the center…) The average balls are about 0.5 mm. a sample (Generally, a sample is a small amount of material, information, or…) of washed and sieved sediments at 125 µm (East Sea (The term sea covers several facts.) from Weddell, Antarctica).

Possible use of modern foraminifera

Ubiquitous in marine environments, they occupy a large number of ecological niches (from swamp (In geography, a swamp is a kind of landscape formation, with little rest…) marine to the abyssal plains). Because of its short life cycle (1 to 3 Month (A month (from lat. mensis “month”, and formerly plural “menstruation”) is a period of time…) in You know? (Average is a statistical measure that characterizes the elements of a set of…)1 year max), foraminifera react rapidly to changes in environment (Environment is everything that surrounds us. It is all natural elements and…). Their population can increase or decrease, their diversity can change, cells can grow or shrink … pollution (Pollution is defined as what makes the environment unhealthy. The definition varies depending on…) Environmental changes (eg climatic changes) can lead to a drastic shift in foraminifera groups. Thus, its short life cycle and ubiquitous presence in the marine environment, are associated with a great sediment richness (analyses Statistics (Statistics is a formal science, method and technique. It is…) powerful), which is an inexpensive and easy method for analysis and Effect (TRACE is a NASA space telescope designed to study the relationship between…) In the fossil (fossil (derived from the Latin verb noun fodere: fossil, literally…) (Study is allowed before environment modification) Make foraminifera, particularly benthic ones, good biomarkers of environmental quality or agents of environmental changes.