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33-885: The Frontenac Arch Biosphere is located in the Thousand Islands - Frontenac Arch area, in one of the great crossroads of Eastern Canada. An ancient granite bridge, called the Frontenac Arch, runs from the northern Canadian Shield in Algonquin Park to the Adirondack Mountains in the United States . The granite arch intersects with the St. Lawrence River in the southernmost part of the Frontenac Arch Biosphere boundary, as

66-644: A free content work ( license statement/permission ). Text taken from UNESCO - MAB Biosphere Reserves Directory​ , UNESCO, UNESCO. Thousand Islands - Frontenac Arch The Thousand Islands – Frontenac Arch region or the Frontenac Axis is an exposed strip of Precambrian rock in Canada and the United States that links the Canadian Shield from Algonquin Park with

99-708: A supereon , but this is also an informal term, not defined by the ICS in its chronostratigraphic guide. Eozoic (from eo- "earliest") was a synonym for pre-Cambrian , or more specifically Archean . A specific date for the origin of life has not been determined. Carbon found in 3.8 billion-year-old rocks (Archean Eon) from islands off western Greenland may be of organic origin. Well-preserved microscopic fossils of bacteria older than 3.46 billion years have been found in Western Australia . Probable fossils 100 million years older have been found in

132-595: A large mountain chain of the ancient supercontinent of Rodinia . There is also a meteor crater near Holleford , where the shield meets the limestone plains of southeastern Ontario. The area is distinctive for having tree species typically found further south, and reaching their northern limits. One example is pitch pine ( Pinus rigida ). Shallow soils and recurring fire have also produced unusual fire barren communities. These provide habitat for rare plants, such as bear oak ( Quercus ilicifolia ) and deerberry ( Vaccinium stamineum ), as well as rare animals, such as

165-735: A possible 2450 Ma red alga from the Kola Peninsula , 1650 Ma carbonaceous biosignatures in north China, the 1600 Ma Rafatazmia , and a possible 1047 Ma Bangiomorpha red alga from the Canadian Arctic. The earliest fossils widely accepted as complex multicellular organisms date from the Ediacaran Period. A very diverse collection of soft-bodied forms is found in a variety of locations worldwide and date to between 635 and 542 Ma. These are referred to as Ediacaran or Vendian biota . Hard-shelled creatures appeared toward

198-505: Is a wide array of wetlands, ranging from larger marshes along the St. Lawrence river, to smaller marshes and bogs along water courses, and large numbers of beaver ponds. The cycles in vegetation in beaver ponds contribute to further wetland diversity; depending upon the amount of beaver activity, there may be open water, marsh, wet meadows or shrub thickets. Some lakes in the area, such as Bob's Lake, also support uncommon species of turtles, such as

231-664: Is known to occur during the RNA replication of extant coronaviruses . Evidence of the details of plate motions and other tectonic activity in the Precambrian is difficult to interpret. It is generally believed that small proto-continents existed before 4280 Ma, and that most of the Earth's landmasses collected into a single supercontinent around 1130 Ma. The supercontinent, known as Rodinia , broke up around 750 Ma. A number of glacial periods have been identified going as far back as

264-612: Is one of four ecoregions of the Mixedwood Plains . The Thousand Islands in the Saint Lawrence River have a distinctive flora and fauna and are a part of the biological corridor. The bedrock is mostly gneiss , granite , and marble , more than a billion years old. The Frontenac terrain is the youngest of the Ontario portions of the arch, dated at 1.2 billion years old. These rocks were once part of

297-526: Is small, it has many Frontenac Arch species mentioned above, including deerberry, Blanding's turtle, and five-lined skinks. Further north, there is still a large gap in the ecological link to Algonquin Park . In this gap are smaller parks such as Frontenac Provincial Park and Bon Echo Provincial Park . Precambrian The Precambrian ( / p r i ˈ k æ m b r i . ə n , - ˈ k eɪ m -/ pree- KAM -bree-ən, -⁠KAYM- ; or Pre-Cambrian , sometimes abbreviated pC , or Cryptozoic )

330-668: Is the earliest part of Earth's history , set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian , the first period of the Phanerozoic Eon , which is named after Cambria , the Latinized name for Wales , where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian is an informal unit of geologic time, subdivided into three eons ( Hadean , Archean , Proterozoic ) of

363-521: Is thought that the Earth coalesced from material in orbit around the Sun at roughly 4,543 Ma, and may have been struck by another planet called Theia shortly after it formed, splitting off material that formed the Moon (see Giant-impact hypothesis ). A stable crust was apparently in place by 4,433 Ma, since zircon crystals from Western Australia have been dated at 4,404 ± 8 Ma. The term "Precambrian"

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396-731: Is used by geologists and paleontologists for general discussions not requiring a more specific eon name. However, both the United States Geological Survey and the International Commission on Stratigraphy regard the term as informal. Because the span of time falling under the Precambrian consists of three eons (the Hadean , the Archean , and the Proterozoic ), it is sometimes described as

429-739: The Adirondack Mountain region in New York , an extension of the Laurentian mountains of Québec . The Algonquin to Adirondacks region, which includes the Frontenac Axis or Arch, is a critical linkage for biodiversity and resilience, and one with important conservation potential. The axis separates the St. Lawrence Lowlands and the Great Lakes Lowlands . It has many distinctive plant and animal species. It

462-534: The Huronian epoch, roughly 2400–2100 Ma. One of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a " Snowball Earth ". The atmosphere of the early Earth is not well understood. Most geologists believe it was composed primarily of nitrogen, carbon dioxide, and other relatively inert gases, and

495-560: The Man and the Biosphere Programme : The reserve's surface area (terrestrial and marine) is 220,973 hectares (853.18 sq mi). The core area is 5,073 hectares (19.59 sq mi), surrounded by buffer zone(s) of 15,900 hectares (61 sq mi) and transition area(s) of 200,000 hectares (770 sq mi). The topography of the biosphere reserve is rugged, consisting of steep, rocky slopes and ridges, typical of

528-526: The St. Lawrence River runs southwest to northeast from Kingston to Brockville . The Biosphere Reserve operates as a not-for-profit network, called the Frontenac Arch Biosphere Network, with over 100 regional partners, and a suite of programs aimed at encouraging the community to become a global model for sustainable development. The Frontenac Arch Biosphere’s activities are guided by three core functions as set by UNESCO and

561-522: The geologic time scale . It spans from the formation of Earth about 4.6 billion years ago ( Ga ) to the beginning of the Cambrian Period, about 538.8 million years ago ( Ma ), when hard-shelled creatures first appeared in abundance. Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history , and what is known has largely been discovered from

594-523: The heron family and listed as a species of special concern, the great blue heron ( Ardea Herodias ), the osprey ( Pandion haliaetus ), the common loon ( Gavia immer ), the bald eagle ( Haliaeetus leucocephalus ) and the pine warbler ( Dendroica pinus ). The main traditional industry in the inland part of the biosphere reserve is agriculture. Other main economic activities include fishing, forestry and mining. Water-oriented recreation and tourism are major economic sectors in shoreline communities along

627-511: The map turtles and Blanding's turtles . Where there is marble bedrock, or other sources of calcium, fens may arise. These often have unusual calcium dependent wetland plants. A southern portion of this region was designated a Biosphere Reserve by UNESCO in 2002, the Frontenac Arch Biosphere Reserve . Within this biosphere reserve is the relatively small St. Lawrence Islands National Park . Although it

660-482: The oxygen catastrophe . At first, oxygen would have quickly combined with other elements in Earth's crust, primarily iron, removing it from the atmosphere. After the supply of oxidizable surfaces ran out, oxygen would have begun to accumulate in the atmosphere, and the modern high-oxygen atmosphere would have developed. Evidence for this lies in older rocks that contain massive banded iron formations that were laid down as iron oxides. A terminology has evolved covering

693-401: The 1960s onwards. The Precambrian fossil record is poorer than that of the succeeding Phanerozoic , and fossils from the Precambrian (e.g. stromatolites ) are of limited biostratigraphic use. This is because many Precambrian rocks have been heavily metamorphosed , obscuring their origins, while others have been destroyed by erosion, or remain deeply buried beneath Phanerozoic strata. It

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726-660: The Precambrian Shield. These alternate with moist forest or wetland valleys inland, and rocky promontories in the Saint Lawrence River known as the Thousand Islands. First Nations call the Frontenac Arch the "backbone of the mother"– Mother Nature’s spinal column. Five separate forest regions meet at the crossroads of the Frontenac Arch and the Saint Lawrence River, creating a rich ecosystem of plant, insect and animal species, renowned as

759-524: The Saint Lawrence River, the Rideau Canal and Charleston Lake . The Thousand Islands, the Frontenac Arch region and the Saint Lawrence River have a long history of human habitation. Archaeological sites found in the Thousand Islands indicate that people visited the area as early as 7,000 years ago, and that Laurentian and Point Peninsula cultures used the area as hunting and fishing grounds. [REDACTED]  This article incorporates text from

792-401: The current scheme based upon numerical ages. Such a system could rely on events in the stratigraphic record and be demarcated by GSSPs . The Precambrian could be divided into five "natural" eons, characterized as follows: The movement of Earth's plates has caused the formation and break-up of continents over time, including occasional formation of a supercontinent containing most or all of

825-453: The early years of the Earth's existence, as radiometric dating has allowed absolute dates to be assigned to specific formations and features. The Precambrian is divided into three eons: the Hadean (4567.3–4031 Ma), Archean (4031-2500 Ma) and Proterozoic (2500-538.8 Ma). See Timetable of the Precambrian . It has been proposed that the Precambrian should be divided into eons and eras that reflect stages of planetary evolution, rather than

858-705: The end of that time span, marking the beginning of the Phanerozoic Eon. By the middle of the following Cambrian Period, a very diverse fauna is recorded in the Burgess Shale , including some which may represent stem groups of modern taxa. The increase in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life. While land seems to have been devoid of plants and animals, cyanobacteria and other microbes formed prokaryotic mats that covered terrestrial areas. Tracks from an animal with leg-like appendages have been found in what

891-505: The five-lined skink ( Plestiodon fasciatus ) and gray rat snake ( Pantherophis spiloides ). There is high bird diversity, including the cerulean warbler , considered nationally endangered owing to the destruction of forests. Although the most important factor producing the fauna and flora is likely the bed rock, the moderating effect of the Great Lakes may also be factor. Also, some northern species extend their range south, drawn by

924-541: The landmass. The earliest known supercontinent was Vaalbara . It formed from proto-continents and was a supercontinent 3.636 billion years ago. Vaalbara broke up c. 2.845–2.803 Ga ago. The supercontinent Kenorland was formed c. 2.72 Ga ago and then broke sometime after 2.45–2.1 Ga into the proto-continent cratons called Laurentia , Baltica , Yilgarn craton and Kalahari . The supercontinent Columbia , or Nuna, formed 2.1–1.8 billion years ago and broke up about 1.3–1.2 billion years ago. The supercontinent Rodinia

957-464: The most biodiverse region in Canada. It has a long and rich cultural heritage and serves as the gateway through which the Saint Lawrence River flows into Canada. Characteristic species of the area include the pitch pine ( Pinus rigada ), the black rat snake ( Pantherophis spiloides ) – Canada’s largest reptile and a threatened species, the least bittern ( Ixobrychus exilis ) – the smallest member of

990-809: The rugged granite landscapes of the Canadian Shield. The basic ecosystem type of the area is temperate deciduous forest . The area has a long history of logging, which has depleted these forests of larger trees. Settlement tends to have occurred in the areas of deeper soil, and fire has particularly influenced the uplands. Reference to the forest descriptions of early surveyors has documented decline in species such as hemlock, which were preferentially removed for leather tanning. Criteria for restoring these forests have been established, and include increased tree size, spring ephemeral abundance, and coarse woody debris. Pollen cores from Lanark County provide information about longer term trends in forest cover. There

1023-526: The same area. However, there is evidence that life could have evolved over 4.280 billion years ago. There is a fairly solid record of bacterial life throughout the remainder (Proterozoic Eon) of the Precambrian. Complex multicellular organisms may have appeared as early as 2100 Ma. However, the interpretation of ancient fossils is problematic, and "... some definitions of multicellularity encompass everything from simple bacterial colonies to badgers." Other possible early complex multicellular organisms include

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1056-482: Was lacking in free oxygen . There is, however, evidence that an oxygen-rich atmosphere existed since the early Archean. At present, it is still believed that molecular oxygen was not a significant fraction of Earth's atmosphere until after photosynthetic life forms evolved and began to produce it in large quantities as a byproduct of their metabolism . This radical shift from a chemically inert to an oxidizing atmosphere caused an ecological crisis , sometimes called

1089-852: Was mud 551 million years ago. The RNA world hypothesis asserts that RNA evolved before coded proteins and DNA genomes. During the Hadean Eon (4,567–4,031 Ma) abundant geothermal microenvironments were present that may have had the potential to support the synthesis and replication of RNA and thus possibly the evolution of a primitive life form. It was shown that porous rock systems comprising heated air-water interfaces could allow ribozyme - catalyzed RNA replication of sense and antisense strands that could be followed by strand-dissociation, thus enabling combined synthesis, release and folding of active ribozymes. This primitive RNA replicative system also may have been able to undergo template strand switching during replication ( genetic recombination ) as

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