Importantly, Sandberg says we should be able to see signs of an aestivating civilization, even though they're dormant.
|
|
Introduced Theba pisana snails aestivating on a row of fence posts in Kadina, South Australia Numerous individuals of the snail Cernuella virgata aestivating on a wire fence near Glanum, in the south of France.
|
|
Commonly, such species have the remarkable habit, which also occurs in some other coccinellid subfamilies, of migrating tens of kilometres to the highest point on a nearby ridge or peak, hibernating or aestivating in masses.
|
|
The most likely explanation for the association as of 2013 is that the Thrinaxodon tolerated the Broomistega or was unable to remove it, possibly because it was aestivating. As is the case with many modern amphibians, the Broomistega probably entered the burrow to seek temporary shelter. During the Early Triassic the Karoo Basin was seasonally arid, so the Thrinaxodon may have been aestivating to conserve energy during a time when resource availability was low and the normally aquatic Broomistega may have entered to burrow to escape the hot and dry conditions of its environment.
|
|
Skin is laterally smooth and with small warts. Body is slender and half cylindrical with thin limbs. They have extra skin folds that are used to hide their feet while aestivating during dry conditions. Fingers and toes have circummarginal discs.
|
|
Meghalaya, in India, is one of the many places where Amphidromus species can be found. Aestivating Amphidromus roseolabiatus inside sterile fronds of stag horn ferns, Platycerium. Pair of Amphidromus (Syndromus) sp. Red arrows shows protruded vaginal stimulator pilaster (vsp), which may be a stimulating organ.
|
|
In addition to the direct negative effect of Theba pisana feeding on agricultural crops, it also has several other additional effects. It uses the stalks of cereals as aestivating sites, which in turn clogs machinery and fouls produce during mechanical harvesting. According to Quick (1952)Quick H. E. (1952). "Emigrant British snails".
|
|
Large groups of adults of subspecies E. q. rhodosensis can be found on occasion aestivating (sheltering from the summer heat) in Petaloudes, on Rhodes, in a place that has become known as the Valley of the Butterflies.Heath, J. & Maitland, Emmet A. (1985). The Moths and Butterflies of Great Britain and Ireland. Vol.
|
|
Burrows containing aestivating Brachydectes, Gnathorhiza, and Diplocaulus are common in the middle part of the Arroyo Formation, likely indicating a period with a drier climate than the early or late Arroyo. The most common shark remains belong to Orthacanthus platypternus, although teeth from Xenacanthus luederensis are also known from some early Arroyo sites.
|
|
Adults are on wing from June to September. There are possibly two generations per year or one with adults aestivating. The larvae feed on a wide range of herbaceous and woody, low-growing plants including blueberry, clover, dandelion, sweet-fern, and tobacco. Larvae have been reared on Vaccinium, Taraxacum officinale and Comptonia peregrina.
|
|
A cluster of Cochlicella acuta (surrounded by larger rounder Theba pisana) aestivating on a fence post in Kadina, Australia. Shell of Cochlicella acuta This species does well on sandy calcareous soils, and often prefers a coastal setting such as sand dunes. It aestivates by attaching itself to vertical surfaces such as fence posts, tall weeds and so on.
|
|
Other common names include Australian mudfish, mud trout, and mud galaxias. Other scientific names include: Galaxias cleaveri, Saxilaga cleaveri, Saxilaga anguilliforms, and Galaxias upcheri. The genus Neochanna is derived from the Greek neos meaning new and Channa, an Asian genus of aestivating fishes. The species name is derived from the fish's original collector, Mr. F. Cleaver.
|
|
Journal of the Royal Society of Western Australia 93, 13–20. Most commonly known to inhabit ephemeral water sources as it is capable of aestivating in summer in the damp substrate. Also found in a range of conditions from slow-flowing rivers, swamps, freshwater lakes and pools, and road side ditches. It can often be found in and around submerged vegetation in lakes and swamps.
|
|
Also, when dealing with the univoltine or bivoltine species, the infestation is brief, just a few weeks, before the beetle population moves off to aestivate. However, in a region where the biology is well understood, it may be worth spraying the inactive masses of beetles, always bearing in mind that if biologically naive practitioners spray the wrong species of aestivating beetles, the results could be expensive.
|
|
The fish becomes inactive in waters below ; at this temperature they breathe almost no air; however, with increasing temperature their air breathing increases. Their preferred temperature range is between , with the temperature of maximum activity. Air breathing is at a maximum in the range . Herpetologist Wilfred T. Neill reported in 1950 that he unearthed a bowfin aestivating in a chamber below the ground surface, in diameter, from a river.
|
|
Leap of faith: Voluntary emersion behaviour and physiological adaptations to aerial exposure in a non-aestivating freshwater fish in response to aquatic hypoxia. Physiology and Behavior 103, 240-247. They need access to riparian vegetation for spawning, and usually live in river systems with access to the sea, as their larval stage is marine. They tend to be found in lower-elevation streams as unlike other species of Galaxias they cannot climb past waterfalls.
|
|
This toad is largely nocturnal and feeds mostly on insects. It reacts to drought conditions by burying itself in the ground and aestivating, which it has been known to do for up to three years. When heavy rain falls, it emerges to feed and makes its way to nearby water bodies where the males call to attract the females. The eggs are laid in strings and the tadpoles develop with great rapidity before the ephemeral water sources dry up.
|
|
To seal the opening to their shell to prevent water loss, pulmonate land snails secrete a membrane of dried mucus called an epiphragm. In certain species, such as Helix pomatia, this barrier is reinforced with calcium carbonate, and thus it superficially resembles an operculum, except that it has a tiny hole to allow some oxygen exchange. There is a decrease in metabolic rate and reduced rate of water loss in aestivating snails like Rhagada tescorum, Sphincterochila boissieri and others.
|
|
There are more than 200 species of insects in the ACT, though they have been poorly studied. The most famous is the Bogong moth, which aestivates in the Brindabella Ranges above 1300 m. It migrates through the territory in October and March when it is attracted in huge numbers by bright lights in the city, sometimes creating a major nuisance. Aborigines used to visit the mountains in summer to gorge on the fat-rich aestivating moths.
|
|
Nautilus 90: 65-69. suggested tree snails generally prefer trees with smooth bark rather than trees with rough bark, because it would require less energy to crawl over smooth bark. Voss also believed Orthalicus reses reses would prefer smooth bark because it would make it easier for them to form a secure mucous seal when they were aestivating, resulting in lower mortalities from dehydration or accidental dislodgement. Orthalicus reses reses snails are entirely arboreal except when they move to the forest floor for nesting or traveling.
|
|
Even if sufficient oxygen were to remain in the atmosphere through the persistence of some form of photosynthesis, the steady rise in global temperature would result in a gradual loss of biodiversity. As temperatures continue to rise, the last of animal life will be driven toward the poles, and possibly underground. They would become primarily active during the polar night, aestivating during the polar day due to the intense heat. Much of the surface would become a barren desert and life would primarily be found in the oceans.
|
|
The first Canterbury mudfish was described by W J Phillipps in 1926, from a specimen sent to him by Mr A. Burrows, a farmer from Oxford, North Canterbury. They were sent to him "alive in a tin box together with a quantity of damp earth, sent by parcel-post on a journey lasting over thirty hours, and arrived alive and extremely active." Although Mr Burrows reported that he had found the fish aestivating in holes in the bank, the mudfish is named after the farmer rather than burrowing behaviour.
|
|
Feeding primarily on terrestrial plants, these herbivores did not derive their energy from aquatic food webs. According to Olson, the best modern analogue for the ecosystem Dimetrodon inhabited is the Everglades. The exact lifestyle of Dimetrodon (amphibious to terrestrial) has long been controversial, but bone microanatomy supports a terrestrial lifestyle, which implies that it would have fed mostly on land, on the banks, or in very shallow water. Evidence also exists for Dimetrodon preying on aestivating Diplocaulus during times of drought, with three partially eaten juvenile Diplocaulus in a burrow of eight bearing teeth marks from a Dimetrodon that unearthed and killed them.
|
|
This physical contact and aggregation allow the moths to retain body moisture. When the aestivating moths are disturbed, the moths within the area of disturbance briefly spread out and leave the aggregation, dropping excrement when unsettled before quickly returning to the aggregation and re- positioning themselves. While the moths mostly remain dormant during aestivation, there are some periods of activity within the aggregation which are correlated to changes in light intensity. During dawn and dusk, portions of the population become active, first crawling around and spreading out, and then flying out of their shelter into the open.
|
|
C. sativus cataphylls are suspected by some to manifest prior to blooming when the plant is irrigated relatively early in the growing season. Its floral axes, or flower-bearing structures, bear bracteoles, or specialised leaves, that sprout from the flower stems; the latter are known as pedicels. After aestivating in spring, the plant sends up its true leaves, each up to in length. Only in October, after most other flowering plants have released their seeds, do its brilliantly hued flowers develop; they range from a light pastel shade of lilac to a darker and more striated mauve.
|
|
The most common and widely distributed species in Australia is the common yabby (C. destructor). It is generally found in lowland rivers and streams, lakes, swamps, and impoundments at low to medium altitude, largely within the Murray–Darling Basin. Common yabbies are found in many ephemeral waterways, and can survive dry conditions for long periods of time (at least several years) by aestivating (lying dormant) in burrows sunk deep into muddy creek and swamp beds. In New Guinea, Cherax crayfish are found widely in rivers, streams, and lakes, with a particularly high diversity in the Paniai Lakes.
|
|
Theba pisana snails aestivating on Foeniculum vulgare in Montbazin, France Aestivation or æstivation (from , summer, but also spelled estivation in American English) is a state of animal dormancy, similar to hibernation, although taking place in the summer rather than the winter. Aestivation is characterized by inactivity and a lowered metabolic rate, that is entered in response to high temperatures and arid conditions. It takes place during times of heat and dryness, the hot dry season, which are often the summer months. Invertebrate and vertebrate animals are known to enter this state to avoid damage from high temperatures and the risk of desiccation.
|
|
Abstract and full article: The species is associated with large poplars, especially eastern cottonwood (Populus deltoides) growing in moist areas along rivers where there is abundant loose rotting strips of bark near the base of the tree. The length of the forewings is 16–19 mm for males and 17–20 mm for females. The eggs are laid in the spring with adults emerging in late spring and early summer, but mainly aestivating until the fall before becoming active. Adults have been recorded in all months except June, but most records are from October and November in the fall and March and April in the spring.
|
|
Bogong moths were historically used as a food source by Aboriginal tribes located in Southeastern Australia. Tribes would travel to the Australian Capital Territories towards the summits of mountains to harvest moths, where they also met with other Aboriginal tribes, fostering intertribal relations as people gathered and feasted during these harvests. People would travel into the caves and scrape aestivating moths off the walls into nets and dishes using sticks. Once gathered, the moths would be roasted to remove the scales and wings and then either eaten immediately or ground into a paste and made into "moth meat" cakes that would last and could be taken home.
|
|
Broomistega (green) preserved in a fossilized burrow with Thrinaxodon (brown)Despite this support for an aquatic lifestyle, other pieces of evidence show that rhinesuchids were capable of some terrestrial movement. Although rhinesuchids did not possess any adaptations for digging, the poorly-ossified juvenile specimen of Broomistega was found in a flooded burrow which was also inhabited by a Thrinaxodon. Various conditions of the way these animals were preserved indicate that they co-inhabited the burrow peacefully, likely to survive a drought by aestivating (staying in a dormant state during hot and dry conditions). The fact that a Broomistega was able to enter the burrow of a terrestrial animal such as Thrinaxodon indicates that rhinesuchids were not exclusively aquatic.
|
|
The aestivation hypothesis is a hypothesized solution to the Fermi paradox conceived in 2017 by Anders Sandberg, Stuart Armstrong and Milan M. Ćirković. The hypothesis, published on 27 April 2017, suggests that advanced alien civilizations may be storing energy and aestivating (hibernating in times of heat instead of cold), until the universe cools to better make use of the stored energy to perform tasks. As the universe cools, the potential work producible by stored energy can increase by a multiplier of 1030 per Landauer's principle. If the goal of an advanced civilization is to maximize the number of calculations done, to generate information processing for tasks like mass-producing simulations, then aestivation would be purposeful to achieve this end.
|
|
Organisms that aestivate appear to be in a fairly "light" state of dormancy, as their physiological state can be rapidly reversed, and the organism can quickly return to a normal state. A study done on Otala lactea, a snail native to parts of Europe and Northern Africa, shows that they can wake from their dormant state within ten minutes of being introduced to a wetter environment. The primary physiological and biochemical concerns for an aestivating animal are to conserve energy, retain water in the body, ration the use of stored energy, handle the nitrogenous end products, and stabilize bodily organs, cells, and macromolecules. This can be quite a task as hot temperatures and arid conditions may last for months.
|
|