Introduction
A biome refers to an expansive landmass associated with different animals and plants. The features of a given biome rely on the level of precipitation and temperatures that the area receives. Due to exposure to the biome’s conditions for an extended period, the plants and animals adapt to the requirements to enhance their survival. Major biomes within earth include the tropical rainforests, grassland, desert, tundra, chaparral, savanna, boreal forest, and temperate deciduous forest. Each of these biome’s characteristics possesses the same features in any part of the world. The phrase tundra emanates from the Finnish language “tunturia,” which means plain with no trees (Nicklen, P. (2020). The characteristics of this biome are essential in defining the conditions in the arctic. Thorough research on the Artic biome is vital to understanding the area’s geographical features and humans and adaptations to enhance survival in this region.
Geography
Location on the Planet
The Arctic lies within the north pole of the earth, commonly associated with polar conditions of climate, animal, and plant life, among other aspects. The Arctic originates from the Greek word arktos, which means bear (Let’s Talk Science, 2020). The time is also assigned to the northern constellation of the bear. The artic has often been used to refer to the Arctic Circle, a geographical line demarcated at the latitude of 66 degrees and 30 degrees north of the equator. Compared to other biomes, the Arctic Tundra formed 1000 years ago is the youngest. The arctic tundra biome lies in the northern hemisphere within a latitude and longitude of 71.2 degrees North and 156 degrees west (Geodiode, 2020). The coordinates might moderately vary due to the earth’s axial tilt. The arctic biome is estimated to be 11.5 million km2 land covering regions spanning from far northern areas of Alaska, Russia, and Scandinavia, Canada, to the forests in Taiga. The artic biome is estimated to cover around one firth of the earth and is associated with immersed winds, coldness, snow cover, and lack of trees.
Topography/Landforms
The artic ground is categorized as permafrost, which implies a ground that remains frozen for temperatures below 32°F (0°C) or colder for two or more years. In areas of heightened altitude, permafrost covers a few feet beneath the soil’s surface. However, the frozen ground can further extend to a depth of around 683 meters (Geodiode, 2020). These conditions make it unlikely for trees to grow within the arctic biome. However, the flat and occasionally rocky plains tend to support lower plants like bog, grass, small scattered trees, shrubs, and moss (Geodiode, 2020). The Arctic is commonly dark and cold in winter, while the surface layer of frost and snow begins to melt in summer, making the artic muggy. The tundra of the artic encompasses streams, lakes, and swamps.
The landscape features of the Arctic are created by permafrost and include ice wedges, pingos, polygons, thermokarsts, and ice wedges. These features can enhance in length or change over the years instead of the millennium or century needed to record such changes in other environments. Continuous permafrost formations are present in southwestern Alaska, where the ground remains frozen everywhere apart from the rivers and lakes. On the other hand, discontinuous permafrost occupies the tundra and forests within northwest Alaska, where the land is only perennially frozen in some places. The topography of the arctic includes thermokarst, made when permafrost melts (Geodiode, 2020). Frozen water takes much space; when it melts, the liquid water takes less space. Land slumps into the void developing a surface depression or what is commonly referred to as thermokarst. Thermokarsts appear as ravines, funnel-shaped sinkholes, caves (during initial stages of melting), or valleys.
Pingos also make up the topography of the arctic biome. Pingo emanates from am Inupiaq phrase meaning cone-shaped hill or a mound of soil with ice at its core. The average height is around 30 meters high with a 50 meters diameter. These features are present within the discontinuous and continuous permafrost. Pingos develop after drainage or afterward when sedimentation permeates within the tundra lake. The most common pingos within the tundra region are the closed-system pingos. Polygons are also available in areas that experience seasonal frost or permafrost and are developed from contraction cracks extended by ice wedges. Polygons are created when pressure from the ice wedge pushes the soil within the gap upward to create two ridges of around 0.5 meters tall (Let’s Talk Science, 2020). In areas that experience poor drainage, water collects within the Center of the polygon and ice-wedge troughs. After that, the collected water harnesses heat from the sun rays melting the permafrost beneath it, causing further slumping. Water fills the channels, further deepens, and eventually enlarges to form a small lake. A low-center polygon develops when the lake drains or is filled with organic material.
The arctic biome topography also includes Ice wedges created when water fills in a contraction crack in the soil. As winter freezing and extension continue, the ice-wedge expands each progressive year. The ice wedges can enlarge to measure an estimated 10 meters apart and grow to 10 meters below the surface. Some massive ice wedges develop throughout thousands of years and play a critical topographical feature in identifying the arctic biome.
Climate
The atmosphere within the arctic regions tends to change depending on the elevation, latitude, topography, and closeness to the sea. However, generally, the arctic areas share polar features due to the latitude of the biome and restrained solar energy during the months of summer. Though the sun rays might be significant, their ability to warm the arctic is limited to the high reflection from ice and snow. During the winter season, radioactive cooling within the surface is linked to extreme coldness; however, at the height of a few thousand feet above the sea level, temperatures tend to increase to a group of around 17 degrees Celsius (Leonard, 2018). These conditions are prevalent within the north-western Siberia and the polar basin during midwinter. The infections can also be experienced within the Greenland Ice Cap and Yakutia and Yukon’sYukon’s mountainous valets. The lowest ground temperatures that have ever been recorded within Northern America is at Yukon, where it ranged about -68 degrees Celsius.
The arctic climate can be divided into two groups where one group experiences a climate similar to the climate within ice caps where no monthly temperature surpasses zero degrees Celsius. The other climate is the tundra climate, where temperatures maximum temperature recorded within a month don’t surpass ten degrees Celsius. The climate can be classified as polar maritime climate located along the Pacific and Atlantic oceans and within the northern islands. During the winter, the temperature falls significantly low in these regions, with high snowfall. In the polar continental climates, which cover the areas of Siberia, northern Alaska, and Canada, winters tend to be increased with the snowfall being generally light. The Canadian Arctic Archipelago islands fall along with the polar continental climate group. The winters are affected by the area’s proximity to the sea due to the prevalence of thick, unbroken sea ice. In addition, apart from the two climates, transitional areas receive the ”ice” climates (Let’s Talk Science, 2020). This climate includes the climate within the polar basin and the southern region of the tree line.
The artic biome polar continental areas within the far north experience winter during the final days of August, while regions at the tree line experience winters around a month later. The parts temperatures continue to decline up to December intensely. From January to March, the temperatures are uniform, with areas within the central Siberian Arctic receiving average temperatures of around −37 ° while regions within North America are experiencing average temperatures of −29 °C. The lowest temperatures. Winter within the European arctic, Iceland, southwestern Greenland coast, and the Aleutians is associated with strong winds, storms, and increased precipitation in either rain or snow form with average temperatures.
The temperatures within the arctic biome remain uniform across the region. The southern outskirts region experiences monthly temperatures averaging ten degrees Celsius. On the other hand, the continental areas experience a short duration of temperatures averaging 27–32 °C (Let’s Talk Science, 2020). The summer is generally calm in the northern islands and maritime climates adjacent to the oceans. The southern region’s record is around seven degrees Celsius, while temperatures fall to four degrees Celsius in the northern area. The highest temperature (16 °C) is experienced within southwestern Greenland. The maritime regions experience some of the densest cloud and fog cover during the summer. Areas that receive continental winters experience increased precipitation levels within the summer months with light snow showers and rain.
The artic biome receives short growing and frost-free durations. The ice climate is prevalent in Greenland, while the southern regions experience maritime features with massive precipitation, which is accrued to cyclone activities. The prevalence of glacier changes within the arctic biome indicates continued climate change. The degree of warming within the area has significantly risen depending on the latitude, wherein Svalbard temperatures were recorded at eight degrees Celsius during the winter. Climate changes have played a significant role in the depletion of sea ice in southwestern Greenland and Svalbard.
Soils
The soils of the arctic biome contain permafrost that affects its drainage. The region comprises shallow lakes that occupy various parts of the biome. The earth within the biome is made up of vivid patterns that emanate from freezing and thawing. The patterned ground is categorized as pebbles, coarser materials, or polygonal nets. The soils tend to relate to the vegetation cover of the region. Compared to the dirt in the south, arctic soils tend to possess solid zonal features. The tundra soils are highly acidic and poorly drained with an undecomposed layer of organic material. The arctic brown soils are covered by grasslands and drier heath, with permafrost lying deep in the ground.
The soils within the arctic biome are grouped as Cryosols or gelisols based on the classification system employed. These soils are easily eroded with permafrost and shaped by constant freezing and thawing that is prevalent as temperatures change during different seasons. During summer, the thaw digs deep to a depth of around 6 to 12 inches (Let’s Talk Science, 2020). Areas within the lower latitude have soils that are well-drained with vegetation cover. The active layer of the arctic biome soil experiences biological activities like animal burrowing, root growth, and decomposition of organic material. Though the permafrost layer is present within most Arctic biome soils, the freeze-thaw layer is also standard across areas like the alpine and arctic biome.
Biota
Flora
The area below the tree limit within the arctic is covered with coniferous forest and merges with treeless tundra vegetation. The white and black spruce occupies parts of North America, while the European larch is the common tree species (Fries-Gaither, 2019). The cottonwoods trees are also common within the lower areas like the rivers within the Arctic biome. In the low Arctic, the primary vegetation includes shrub birch, tall-shrub tundra, willow, Labrador tea, alder, cranberry, and Arctic heather, present in the wetter areas. The ground cover within the arctic is mainly covered with mosses and lichens; cushion plants are also common within the uplands of the biome.
The high Arctic is covered with less vegetation than the areas within the low arctic. The tall arctic bears only half of the vascular plants common within the low arctic of North America, which records around 600 species of plants. Areas within the higher regions like Greenland and Ellesmere Island contain around 100 species of vascular plants (Fries-Gaither, 2019). This phenomenon’s primary reason is the prevalence of drier conditions, cooler summers, and limited growing seasons. The distribution of around 40% of vascular plant species within the high arctic can be termed as circumpolar. Some of the crucial plant species in the arctic are the prostate willows which help hold snow cover beyond the northernmost parts of the biome. The websites of the biome are covered mainly with sedge-moss meadows. The uplands are patchily surrounded by prostate willows, grass, and mat-forming dryas.
The coastal region of the biome depicts the actual characteristics of a polar desert. In the areas near the Arctic Ocean and the land at a few hundred meters elevation in the arctic, lack of sufficient soil moisture and poor soil development makes it impossible to grow plants. The rare plants in this region grow within frost cracks where fine soil deposits and snow are captured. These plants include the Arctic poppy, small saxifrages, and some rushes adapted to these conditions. Some flowering herbs and the Arctic poppy make some rare types of flowers categorized as solatropic (Fries-Gaither, 2019). This type of flower shows the response to the sun, where their blossoms tend to follow the sun’s movement to focus the solar heat in ovary development. The flowers also attract insects attracted to the warmth to ensure maximum pollination and hasty action of seeds.
Fauna
The ecosystem within the arctic biome does not have the richness and diversity of different species common within the tropical and temperate ecosystem. The number of plants and animals tends to reduce as the latitude in the polar areas increase. The conditions within the tundra region support birds and mammals only. The arctic biome has been recorded as a habitat for an estimated 100 bird species and 20 species of mammals (Fries-Gaither, 2019). The majority of the fauna within the arctic tundra is circumpolar in distribution. For instance, the wild reindeer in Eurasia belong to the same species as the caribou of North America.
Similarly, the lemmings present in Greenland and North America belong to a different species but are closely related to those in Eurasian Arctic. The similarity within the arctic biome fauna results from the reduced sea levels during the Pleistocene glaciations. During this period, a vast land linkage referred to as the Bering Land Bridge linked Alaska to Siberia.
Various types of herbivores reside in the arctic tundra like the reindeer, caribou, and muskox; Arctic hare, colored and brown lemmings, and the arctic fox rarely live outside the tundra environment. Different species of shrews, ground squirrel, red fox, wolves, the arctic hare, wolves, vole, ermine, brown bear, and collared and brown lemmings are present in the arctic tundra as well as other ecosystems. Limited species have penetrated and survived the low arctic tundra and settled in areas habitable. Some of these species include the snowshoe hare and the moose in North America. The migration of the animals to areas is attributed to the development of willows and shrubs in the habitats and the warming climate. Marmots and other species of the mountain sheep have also further raised their settlement to a certain location within the arctic tundra.
Areas within the high arctic tundra above 80° N comprise northernmost Greenland, Canadian arctic islands such as Ellesmere and Axel Heiberg, northern areas of Franz Josef Land and Svalbard; only limited mammals manage a viable population. The Peary caribou, Arctic hare, musk ox, and collared lemming are the main herbivores in the High Canadian Arctic. The predators of the herbivores, which include ermine, wolves, and arctic fox, are also present in the region. The species are also common in Greenland, with the caribou being present in the area for a long time (Fries-Gaither, 2019). The Arctic fox and caribou are the native species in Svalbard, while the Arctic fox is also common within the Franz Josef Land. The polar bear is also associated with the arctic tundra, where it preys on seals, nesting birds, and other land mammals.
Only a few birds permanently reside within the Arctic biome; the snowy owl, raven, gyrfalcon, and ptarmigan list these species. The rest of the species tend only to visit the tundra during the summer to breed and raise the young ones. These species later migrate towards the tropical, temperate, or within the maritime regions during winter. Though birds have been able to access some areas commonly inaccessible to mammals, their location is influenced by migration routes and wintering zones. The routes of migration commonly used by waterfowl and the shorebirds are found along coastlines, with some bird species crossing over vast water bodies. Nonetheless, the North Atlantic provides a partial blockage creating circumpolar interbreeding, thereby creating high uniformity among the birds in eastern Eurasia and western North America.
Some of the most prevalent nesting birds within the Arctic tundra include the waterfowl, shorebirds, and passerine species of birds. The riparian habitats and the areas with high shrub density hold some of the great populations of passerine species. As the latitude within the arctic tundra increases, birds’ species reduce. The snow bunting and the redpoll make the only group of nesting birds prevalent in the northernmost areas of the tundra. Apart from the resident species, there are also other birds like the raptorial birds, which nest within the arctic. These species of birds include the peregrine falcon, short-eared owl, and rough-legged hawk. The golden eagle lives within the mountainous regions of North America, while the White-tailed eagle is common in Eurasia and Greenland (Fries-Gaither, 2019). The jaegers feed on eggs and nestlings of other birds during the mating season, where they nest at the tundra and the barren polar regions. The jaegers spend most of their time at sea and migrate to the tundra during mating and nesting. The artic coastal cliffs are nesting zones for different marine birds like the Alcidae, Laridae, and the Procellariidae species of birds that depend on the ocean for food.
General Human Adaptations
Human adaptations refer to the structural and functional characteristics within the human populations that enhance survival and transform the physical environment during stress or change. The human coping mechanism is associated with cultural, psychological, and behavioral changes to cope with the environment. The analysis of human adaptability to the Arctic biome pays attention to understanding how humans interact with each other, the environment, and how they transform the environment to make it more habitable (Leonard, 2018). The analysis additionally seeks to understand the environment transforms humans. The modern evolutionary theory provides an efficient understanding of human adaptability to a certain environment or habitat.
Modern Evolutionary Theory on Adaptability
The modern evolutionary theory seeks to explain human adaptability by analyzing intricate interactions of phenotypes and genotypes. Genotype entails the hereditary abilities of a given organism, while on the other hand, phenotype refers to the output resulting from the interaction of genotype and the organism’s environment. The theory states that some species portray a limited environmental transformation and show reduced phenotype differences. Organisms such as bacteria can only handle minute changes in changes of their habitat temperature. On the other hand, humans portray heightened phenotypic variations and can withstand a vast degree of environmental conditions.
Some of the primary tenets of the evolutionary theory state that; all populations are committed to increasing their number until a situation where the environment cannot accommodate the population. The other tenet states that all populations undergo genetic transformations through mutation and recombination. Another element of the modern evolutionary theory states that organisms that possess the best-adapted phenotypes are more likely to be selected within a certain set of circumstances. The final tenet of the theory holds that the impact of the environment on genotype is indirect (Leonard, 2018). The adaptive transformations of every organism and humans rely on the hereditary genetic matter passed on from one generation to another generation. The theory further adds that the evolutionary capabilities of a species depend on the organism’s interaction with the environment in its lifetime. The change is gradual; therefore, populations within a certain ecosystem represent earlier conditions within that environment.
According to modern evolutionary theory, some challenges that hinder organisms’ adaptation include gene flow and mutations, difficulties in allocation, physical limitations, evolutionary opportunity, and changing environments. The history of a given organism also affects its future changes hence significant transformations in its anatomy are limited (Leonard, 2018). The degree of animal adaptations also depends on the conditions of the natural world, which are hard to change. As the biological changes of animals are slow, populations hardly adapt perfectly to their current situation. However, there is an exemption on unique cases with long-term environmental stability.
Focus: Human Adaptability to Arctic Biome
The study of human populations’ adaptations within the arctic calls for intense work to understand general human adaptations to adverse ecosystems. The Inuit people who reside within the Arctic biome have undertaken different strategies to adapt to the changing environment like petroleum exploitation, biophysical changes within the Arctic, global climatic changes, and contact with American society. The study analyses the human adaptability within the biome in respect to the cold stress, coping with low biological productivity, and heightened periods of light and darkness. Further analysis of the human adaptability to snow, ice, sea, and the changing Arctic biome ecosystem is crucial in understanding human adaptability at the arctic biome.
Adaptation to Cold Stress
Some of the common adaptive mechanisms adopted by the Inuit to deal with cold stress include cultural and physiological adaptations. Earlier, the Inuit were thought to have body adaptions like high body fat, eye fold features, and facial flatness. However, these morphological features have proven minimal protection to cold stress, which causes frostbite, cold injury, or hypothermia. The Inuit shelter, sharing of body heat, clothes, diet, and sea oil lamps are coping mechanisms against cold stress. The Inuit use their cultural regiments to deal with the cold stress (Leonard, 2018). The clothes have numerous vents where air flows in and out efficiently; the clothes are also made with different layers that collect and warm the air, thereby acting as an insulator. Since the outermost layer is impermeable and windproof, the Inuit clothing retains more heat while keeping moisture away.
The shoes of the Inuit were made from sealskin; the stocking made from the Arctic hare fur with grass-thatched between the sole and the stockings to absorb moisture. The Inuit Igloo houses were also designed to withstand the cold stress. The Igloo is made using insulating materials with limited exposure to external surface areas. It is also designed to reflect heat from internal heat sources to keep the occupants warm. Another adaptation employed by the Inuit to deal with cold stress is physiological adjustments. During winter, ice fishing and seal hunting shelters and clothing cannot offer a reliable solution for coping with the warmth. Some physiological strategies to deal with the cold include increased basal metabolic rates, vasoconstriction, shivering, oxygen consumption, and acclimatization transformations and behavioral initiatives.
Adaptation to Snow and Ice
The Inuit have diverse ecological knowledge that enables them to determine differences in snow and ice features in minutes before accidents occur. The children of the Inuit, through experiments, learn to recognize any variations in snow and ice characteristics. The education process of the Inuit incorporates the ecological knowledge to help better weather prediction and identification of warnings and patterns of migration of different games. For decades, the art of hunting prey has been passed across generations of Inuit populations living in the Arctic. Scanning the environment, stalking, bringing down prey, retrieving, and sharing the catch were important behaviors taught across generations (Leonard, 2018). These habits played a significant role in enhancing survival amongst populations in inland Alaska, where resources are limited in quality and quantity. The Inuit have developed knowledge identifying that young salt ice is flexible instead of being brittle. Literature by Moran (2018) states that in the event sleds start sinking, the Inuit understand it is better to keep the sled in motion and ride out if they spot a thin ice spot. By interacting with the environment for a long time, the Inuit has recognized color as a distinguishing feature within different types of ocean Ice. The populations have identified the thick and safe ice as grey while the thin and unsafe ice appear dark. By knowing color distinctions between safe and unsafe ice, the populations have managed to live and hunt safely at the Arctic biome, but accidents still occur.
Adaptation to Extended Lightness and Darkness Period
The artic biome is characterized by dynamic cycles of light and darkness. At certain times, the daylight hours significantly change, while the sun never gets to the horizon in times like December. The changes in day and night schedules have a significant effect on the physiological well-being of an individual. In the book, Moran (2018) states that physiological functioning like blood sugar, blood pressure, body temperature, adrenal hormones, hemoglobin levels, pulse, levels of amino acids, and quantity of minerals excreted all follow a 24-hour rhythm.
General principles of human adaptation in extreme environmental conditions are associated with hormonal biorhythms and are essential mechanisms of adaptation to the external environment. They are manifested by changes in the excretion of steroid hormones, which are regulated by seasonal and circadian biorhythms. However, studies of the biorhythms of excretion of steroid hormones can reveal their regulatory features in control groups from the local newcomer population from birth living in a given area and newcomers to the Arctic biome and being at a certain stage of adaptation (Kim et al., 2016). Changes in biorhythms may be associated with gastroenterological pathology (Kim et al., 2016). This must be taken into account when prescribing treatment and in the prevention of exacerbation of the established disease.
The given statements make the conduct of the analysis of circadian rhythm relevant in several aspects. Thus, a comparative analysis of biorhythms in regions of a sharply continental climate, equated to the regions of the extreme Arctic biome, provides a unique opportunity to address a wide range of topics. This also includes their dynamics during the period of stay and at different periods of residence in the adaptation area. Fluctuations in the excretion of steroid hormones are of practical value as markers of the stress of the hormonal system.
External and internal rhythms of the micro and macro environment affect many phenomena and processes. If external rhythmic signs are evident for observation, then some aspects of internal phenomena are still a topic of research. The nature of external rhythms is mainly based on geophysical phenomena. As a result of this process, a number of environmental parameters on the planet are undergoing changes that fit into the basic laws of nature. The main environmental factors of external cyclic rhythms are changes in daily solar radiation, temperature, pressure, and humidity. These parameters also include the earth’s electromagnetic field, sea tides, or seasonal monsoons. It should also be noted that solar activity is influenced by cosmic cyclical rhythms (Leonard, 2018). Changes in solar activity are directly related to changes in climatic conditions on the planet. Undoubtedly, external cycles are primarily related to abiotic factors. Nevertheless, for any organism, they are natural prerequisites for transformation and changes in activity and behavior.
The internal cycles of the body are mainly responsible for physiological rhythms. The rhythm in the physiology of the body can be traced in the metabolism of DNA and RNA synthesis in cells, in the anabolism of proteins, in the work of enzymes, in the synthesis of ATP in mitochondria (Leonard, 2018). It has been proven that the ontogenesis of cells, muscle contractions, the work of the endocrine glands, the heartbeat, respiration, the excitability of the nervous system, that is, the work of all cells, organs, and tissues of the whole organism, fall under a certain cycle. It should be noted that each organ system has its own individual cycle. It is possible to change these rhythms by the influence of environmental factors only within small limits if these factors oppose the basic natural external rhythms.
Nevertheless, all internal cycles represent a common integral system for the organism, subordinate to a common mechanism. Therefore, it is natural that the changes occurring in the process of life of organisms coincide in period with external, geophysical, and cosmic cyclic factors. Such cycles are defined as adaptive biological rhythms, the gradation of which occurs in accordance with the annual and daily movements of the Earth. Changes in the body associated with the diurnal movements of the Earth are defined as circadian cycles, and tidal, lunar, and annual rhythms are defined as circadian rhythms.
Due to the triggering of the circadian mechanism, the most significant metabolic functions work in accordance with the most favorable conditions for this process, limited by daily or annual time frames. In the process of evolution, adaptive biological rhythms or circadian cycles have emerged as a factor in the physiological adaptation of the body to cyclic changes in the environment. The body’s circadian adaptations are fundamentally different from the purely physiological, the function of which is to maintain life support constantly, for example, breathing, blood circulation, and somatic cell division.
Conclusion
In conclusion, human adaptability is outstandingly demonstrated by assessing its adaptation in the conditions of the Arctic biome. It is evident that the harsh conditions of such regions impose significant stress on a wide range of human systems, which is why the adaptation can go to a greater extent in order to accommodate these environments. Considering the scarcity of food, extremely low temperatures, and irregular light cycles, many behavioral, cultural, and physiological changes are needed in order to adapt to such conditions. In addition, human evolution theory is critical to understanding the process of adaptability, which is manifested in the population increase in accordance with environmental limitations as well as the selection on the basis of fitness factors. Specimens with the most suitable cold resistance and less stress-based response to irregular light cycles are likely to survive and have offspring with higher fitness. Cultural adaptations are also relevant since they dictate the key behavioral patterns of survival in the Arctic biomes. Therefore, thorough research on the Artic biome is important to understand the area’s geographical features and humans and adaptations to enhance survival.
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