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76

No, this is not possible. There are a few reasons for that, but most important are that the only thing a mosquito injects is its own saliva, while the blood is sucked into the stomach where it is digested. To be able to infect other people HIV would need to be able to leave the gut intact and then also be able to replicate in the mosquitos which it cannot ...


48

A quick search on Web of Science yields "Polyphasic Wake/Sleep Episodes in the Fire Ant, Solenopsis Invicta" (Cassill et al., 2009, @Mike Taylor found an accessable copy here) as one of the first hits. The main points from the abstract: Yes, ants sleep. indicators of deep sleep: ants are non-responsive to contact by other ants and antennae are folded ...


45

This question falls into different subquestions: 1. How much blood does a mosquito take when feeding? This is not so easy to answer, but there are publications which measure the volume of different mosquito species. Reference 1 lists volumes between 2.85 and 11.99µL per meal and mosquito. Reference 2 lists 3.07 and 5.71µL. To make the approximation a bit ...


33

Off the top of head as a medical professional I can imagine the following mechanisms (everything is just speculative reasoning): Insects don't have blood. Instead, they have hemolymph whose primary role is not oxygen transport (they have an additional tracheal system for this purpose), but rather that of nutrients. Thus they don't need (and don't have) an ...


31

The short answer is apparently yes. Studies on sleep in insects date back to papers published by Phil and Nellie Rau in 1916 and 1938. Hussaini et al. (2003) showed that sleep does affect memory formation in honey bees. They showed that retention of extinction learning is significantly reduced in bees that were sleep-deprived. More about sleep in honeybees ...


29

I believe that MattDMo's hypothesis is incorrect. Only one group of ants, the Attini tribe, cultivates fungus as a food source. This group is exclusively a New World group, thought to have originated in the Amazon rainforest and spread out from there. I see from your profile that you are located in India, which is outside the range of the ...


25

There will always be a tradeoff in terms of resource allocation between reproduction and self maintenance. Since worker ants forego reproduction to perform other roles (gathering resources, caring for young etc.) within the colony, it makes sense that this would favour a longer lifespan. This idea works for most animals (i.e. higher reproduction = lower ...


23

Dickinson (2005) has a good review of insect flight, including behavior, biomechanics, electrophysiology, and neural control with links to more of the primary literature. What follows is a general summary thereof. The jagged trajectories you mention are called saccades in the insect flight literature. In Drosophila, saccades are ~90° turns accomplished in ...


21

There are instances of insect muscle growth in response to increased use. The flight muscles of the tsetse fly (Glossina morsitans) have been observed to grow at a faster rate when subjected to enforced exercise (Anderson and Finlayson, 1976). Also larger mandibular adductor muscles (which power the feeding apparatus), and associated head capsule have been ...


20

It is a result from the insecticide you are using. From this excerpt from the 10th Edition of the Mallis Handbook on Pest Control: Neurotoxic insecticides cause tremors and muscle spasms, flipping the cockroach on its back. A healthy cockroach can easily right itself, but without muscle coordination, the cockroach dies on its back. Cockroaches exposed ...


18

Yes, mantises hunt cicadas... Mantis eating cicada. Source: Dreamstime. ...and yes, orioles hunt cicadas too... Oriole eating cicada. Source: Bird Ecology Study Group. .., and what may be more relevant to your idiom: orioles prey on mantises. Oriole eating mantis. Source: Sustainable Adventure.


17

There are a number of papers studying the ability of fungi to metabolize keratin, the primary structural component of nails (as well as skin and hair). Ants are also known to cultivate fungi for nutrients, so this may simply be a case where the ants are bringing food for their "farm animals."


16

Holometaboly is believed to have evolved only once (Labandeira, 2011), but is arguably the most successful mode of development we know of in terms of species richness (Kristensen, 1999 - PDF link). Insects which have adopted this method are far more diverse than their hemimetabolous counterparts. A conservative estimate by Hammond (1992) is that ...


16

Its definitely a True bug (Hemiptera), and based on its distinct pronotum and small head I'm guessing its a Wheel bug (Arilus cristatus). It is a common species that is also found in Indiana. They are aggresive predators and are part of the family Reduviidae also known as Assassin bugs. Assassin bugs have a painful bite, and they inject a toxin when they ...


16

This is probably a fly killed by the fungi Entomophthora muscae (or closely related) or maybe a Cordyceps fungus. These kinds of fungi mainly attacks insects, and you sometimes see attacks as white, swollen abdomens in flies. (Picture of common infection, from bugguide.net) These fungi are also known to change the behaviour of infected individuals, so ...


16

Short answer Excretion of blood and urine may prevent overheating by reducing body temperature through evaporative coolong (akin to perspiration). Excretion of blood and urine also concentrates the ingested blood. Background Female Anopheles mosquitoes seek blood for nutrients necessary to egg production. The cold-blooded insects may excrete some freshly ...


14

Insect flight muscle is capable of achieving the highest metabolic rate of all animal tissues, and this tissue may be considered an exquisite example of biochemical adaptation. Locusts, for example, may (almost instantaneously) increase their oxygen consumption up to 70-fold when starting to fly. In humans, excercise can increase O2 consumption a maximum ...


14

Both the Forewing as well as the Hindwing of Butterflies are made of thin chitin structures which are pretty thin and sensitive. If you touch the wing with to much force, it may break. Then the upper side of the butterfly wing is covered with small scales - what you called the "dust". This can be seen in this figure (from here): and also in this electron ...


14

That is a hawkmoth, probably Hyles annei (Guerin-Meneville, 1839). It is one of a number of moth species commonly called "hummingbird," "sphinx," or "hawk" moths in the family Sphingidae. Beautiful, isn't it? :) edit - sorry, I originally misidentified this as Hyles lineata - the pattern is slightly different.


14

There are a number of environmentally destructive methods that would be effective, including draining the lake, covering the surface with a continuous layer of oil, or adding toxins to the water, but I'm assuming you're looking for a method that will have the minimum possible off-target effect. Different mosquito species breed in different habitats and are ...


13

Studies of Deinococcus radiodurans, the most radioactively tolerant microorganism we know, show that it has many genes for DNA repair. In the case of the cockroach, I would assume that in addition to repairing genes, and maybe some antioxidants produced in the cells to quench free radicals produced by radiation, the fact that the roaches lay many, many ...


13

I'm not 100% sure, but I think they look like scale insects (Coccoidea). In particular it looks at bit like a hermaphrodite cottony cushion scale insect (Icerya purchasi)... The white fluffy thing underneath the insects is the ootheca (egg case). The mature insect migrates to the main trunk of its host tree and attaches to the bark. It then secretes the ...


13

It's a larvae from a ladybird (or ladybug). Judging by the stripe pattern it is a Common Spotted Ladybird (wiki: Harmonia conformis) and from the body shape & size I'd also say 3rd instar. The one you have photographed, and the one on flickr, are larval forms of the ladybug, just like when a catepillar becomes a butterfly, the ladybugs also have a ...


13

Looks like the nymph of a masked hunter. They carmouflage in dust and sand.


13

It's a kind of assassin bug, specifically a Masked Hunter: The surface of an immature Masked Hunter is sticky and it attracts lint and dust which helps to camouflage this predator. and The name refers to the fact that its nymph camouflages itself with dust. Though they feed on small insects, they will bite defensively, and when they do, it's ...


13

A mosquito's proboscis isn't like that of a butterfly, which could easily have nectar clinging to it when it is coiled up; instead, consider that the part of the mosquito's proboscis that enters a blood vessle is probably wiped clean when it is retracts outward through the epithelium. A a dirty needle or razor is many, many times larger than the sucking ...


12

Certainly ants evolved from insects that could fly. All the earliest wasps (ants are specialized wasps) could fly. Building and maintaining wings is expensive in terms of energy. That's an obvious evolutionary advantage to not having wings. So if there's insufficient benefit from having wings then there's selective pressure against having wings.


12

After seeing your question, I decided to do a bit of research on the topic. First Source: EurekAlert! http://www.eurekalert.org/pub_releases/2007-04/jws-mrt041607.php "Mosquito repellents that emit high-pitched sounds don't prevent bites" Some key-points from the webpage: A Cochrane Systematic Review of the use of electronic mosquito ...


12

The Cicada A careful study of the noise-making apparatus of the cicada can be found in a 1994 paper by Young and Bennet-Clark.$^1$ The authors generated sounds at about 0-16 kHz at peaks on the order of 100 dB using cicadas in various stages of deconstruction. The cicada uses a resonant organ-system called the tymbal which buckles and unbuckles rapidly to ...


12

This is mostly a guess and loose suggestion, since the picture is not very clear (would need to see the larvae in more detail). However, Bagworm moths (Psychidae), Case moths (Coleophoridae) and Caddisfly larvae (Trichoptera, almost exclusively aquatic) all build similar cases. They construct their cases out if silk and often include debris, pebbles and ...



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