Invertebrates - Animal Questions.org

Do Bees Die in the Winter?

The survival of bees throughout the cold months of winter is largely dependent upon what particular species the bee belongs to. The social bees do not hibernate in the south such as birds do; instead they live or die in their natural environments. Honeybees usually do not die in the winter, while bumblebees do. In winter the queen bee will stop laying eggs so numbers in the hive will be reduced by deaths due to old age, she will then find a sheltered place to stay during the winter while all other bees die as the cold weather comes.

Usually in the winter the queen bee can be found burrowing in a well drained sandbank or taking up occupancy in an abandoned mouse nest. Once she has settled into her nest, she then begins to make beebread from the nectar and pollen she has collected over the summer. She then dumps the load and lays eggs on it. As a final step she covers it with wax and relaxes atop it hibernating for the winter until springtime. In the spring the queen bee will begin laying again to bring the bee’s numbers back up.

How Do Crabs Breathe?

Crabs are somewhat similar to fish in that they are equipped with gills for breathing. The gills themselves are feathery type structures located at the top of the crab’s walking legs. They are derived from part of the jointed walking leg. In order to breathe on land, crabs must keep these gills moist so that oxygen in the air can still be absorbed. Gills work because oxygen is a very small molecule. During respiration these oxygen molecules first dissolve into a layer of moisture surrounding a thin membrane. Then these molecules, (because they are so small) cross through the membrane and enter the circulatory system (blood) of the crab. The source of oxygen can then either be used as gas in the air or already dissolved into another liquid such as the sea.

It does not necessarily matter where the oxygen originally comes from as much as that the surface of the oxygen molecules cross is wet. Crustaceans that reside in the water do not typically have trouble when it comes to keeping their gills moist. Terrestrial crustaceans can usually keep their gills wet by using fluids from inside of the body and by having their protective chambers well sealed so that very little moisture is lost. Crabs such as the hermit crab use their claws and antennae to keep themselves moist by placing water onto themselves.

Because these creatures need to keep their gills moist to breathe properly, it is important that a water source of some kind always be nearby. One of the most common reasons crabs such as the hermit crab dies in captivity is because crab owners neglect to provide them with this. The difference between marine crabs and land hermit crabs is that land hermit crabs have much smaller gills but also need air to breathe. They must be kept moist to survive but would drown if submerged completely in water. This is why it is also important when keeping them in captivity to provide a broken up piece of sponge in their water dish so that they have something to grasp onto to keep from losing their footing and falling into the water and/or drowning. If the crab’s gills become too dry, the crab will die. Another interesting fact about hermit crabs is that they carry an extra supply of water around in their shells to help keep them moist.

Are Snails Hermaphrodites?

Not all snails are hermaphrodites. However the majority of snails are. Snails are able to reproduce differently than almost any other type of creature because they are equipped with both male and female reproductive organs. This is especially consistent among land snails and most marine snails as well. The only snails currently known to not have adapted this attribute yet include some freshwater and marine species such as the Apple snail and the Periwinkle snail. These two types of snails still have separate male and female species.

All snails are considered to be sexually mature by the time they reach the age of one. This is because the life span of many species does not often last for more than 5 to 7 years, allowing for a faster growth rate of the species. This make up of the snail will include their reproductive organs that are located on the side of their body. This is close to the top of their body as well, which allows for easier abilities to mate and for the baby snails to grow.

In biology the term hermaphrodite is used to describe organisms that have reproductive organs associated with both the male and female species. Many taxonomic groups of animals such as invertebrates do not have separate sexes. Therefore, in these groups hermaphroditism is a normal condition and simply a way of life for these creatures. This enables a form of sexual reproduction in which both partners can act as the “male” or the “female”.

The great majority of pulmaonate snails, opisthobranch snails and slugs are hermaphrodites. This hermaphroditic trait is also found in some fish species and to a lesser degree in other vertebrates. Most plants are hermaphrodites as well. Historically speaking, the term hermaphrodite was often used to describe ambiguous genitalia and gonadal mosaicism in individuals of gonochrist species, especially human beings. This word hermaphrodite entered the English lexicon during the 15th century and is derived from the Greek Hermaphroditos, a combination of the names of the gods Hermes (male) and Aphrodite (female).

Self-fertilization is also obviously a common practice among snails. For snails that do mate, since they are hermaphrodites they mate differently than other types of animals. When it comes time for them to mate they begin to produce a mucous covered calcerous beforehand that pierces the skin of their mate. Sometimes this is also referred to in snail terms as a “love dart”. The mucous contains a pheromone that makes the female reproductive canal less hostile to sperm. All hermaphroditic snails are able to lay eggs. They can do this as mentioned above by “mating” with themselves or by reproducing with a mate. Many have been known to breed sexually as often as possible. Snails that are not hermaphrodites can only reproduce sexually and usually give live birth rather than lay eggs.

The population of giant carnivorous hermaphrodite snails is on the rise in places like New Zealand. These carnivores can live up to 20 years of age and also lay eggs that resemble small bird’s eggs. They dwell on damp forest floors and forage for their food at night, mainly preying on earthworms. However they have also been known to eat slugs from time to time using the row of sharp, backward facing teeth that they are equipped with to grab their prey and devour it using digestive enzymes. Because this species of snails are hermaphrodites, any adult snail is able to mate with any other adult snail. This species has been a victim to endangered habitats and natural enemies in older years, but the conservation efforts in areas such as Hawke’s Bay in New Zealand are proving to be quite beneficial in bringing their numbers back up.

Is There a Species of Jellyfish That is Immortal?

The species of jellyfish known as turritopsis nutricula may be the only animal in the world to become immortal. This creature is a hydrozoan (a taxonomic class of very small, predatory animals which can be solitary or colonial and which mostly live in saltwater). This hydrozoan’s jellyfish form can revert back to the polyp stage (its first stage of life) after becoming sexually mature. It is the only known case of a metazoan capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary stage. It does this through the cell development process of transdifferentiation. Cell transdifferentiation is when the jellyfish alters the differentiated state of the cell and transforms it into a new cell. During this process the medusa of the jellyfish is transformed into the polyps of a new polyp colony.

When the jellyfish transforms its umbrella first reverts itself and then the tentacles and mesoglea break down. The reverted medusa then attached itself to the substrate by the end that had been at the opposite end of the umbrella and starts giving rise to new polyps to form the new colony. Theoretically speaking, this process could go on forever effectively rendering this particular species of jellyfish biologically immortal. Although in nature, it is very rare for turritopsis to ever revert to the polyp stage as many succumb to predation or disease during the plankton stage.

It has been said that it is currently impossible to estimate the age of an individual jellyfish as no single specimen has ever really been observed for an extended period of time. And even if this species does have the potential for immortality, there is no laboratory evidence of many generations surviving from any individual. Scientists are still trying to study this magnificent creature to discover how it is able to reverse the aging process. Because they are able to escape death, the number of this particular species is continuing to grow and they are now found worldwide in oceans around the globe rather than just their native Caribbean waters.

Do Spiders Hibernate?

Whether spiders hibernate or not is dependent upon the particular species that spider is. For instance spiders such as the garden orb weavers, different widow varieties and argiopes only live during one season and die during the winter, leaving behind thei egg sac for next season. Other species such as the fishing spider or the tarantula that typically live longer, may hibernate in winter by spending their time underneath the bark of trees or rocks, in cellars, attics, etc. Some adults even survive by preparing a winter nest of silken webbing under loose bark within which they are insulated from the cold.

In several species of spiders, young spiderlings hatch out and then remain in a communal webbed egg sac through the winter. Those spiders that hibernate in leaf litter and rock piles are not usually found to be in a deep sleep and on mild winter days may be found crawling about in search of insect food that is plentiful and easy to secure in its dormant state.

Can Bees Sting More Than Once?

There are about 20,000 known species of bees. Some bees are able to sting a victim more than once, while others can only sting once and usually die after doing so. It just depends on the species.

Bees store their venom in sacs attached to their stinger and only female bees are able to sting. The stinger is part of the female bee’s reproductive design. Certain species of bees die after stinging because these stingers are attached to their abdomen and have hooks on them. When the bee tries to fly away after stinging something, part of its abdomen is ripped away resulting in its demise.

Honeybees and killer bees are only able to sting their victims once, while bumble bees can sting more than once because their stingers are smooth and do not get caught in the victim’s skin when they go to fly away. Carpenter bees are also able to sting over and over again due to their stingers not being hooked or barbed.

Do Spiders Drink Water?

Most spiders do drink or require a regular daily amount of water. In the wild, most spiders will drink from any available source such as droplets on vegetation or the ground or from early morning dew that has gathered upon their webs. If a spider is kept in captivity it is good to provide them with a fresh water source such as in a small bottle cap or a damp sponge for smaller species, and a small dish for larger species.

It is a myth that spiders live in drains. When you find a spider in a building or in the shower, it is usually because it’s a good source of water for them and then they typically remain trapped because the sides are too slippery or steep for them to climb back out.

Depending on the species, different spiders may use different methods to quench their thirst. The whistling spider which resides in the desert, covers its burrow with a thin layer of silk to keep it humid and dew or raindrops are captured using a silk covered mound near the entrance. Some species of spiders ingest nectar, while others quench their thirst by drinking dew drops in early morning.

A common practice for many species of spiders to follow as a way to get their regular intake of water is to consume their spider web first thing every morning. By doing this they consume water that has condensed as droplets onto the web. Other spiders may use their pincers to take water from their webs and place it into their mouths.

While, spiders such as the black widow and the red back do not drink water at all. Instead they get all of the fluid that they require by sucking the juices from their prey.

Are Bees Out at Night?

Most stinging insects are semi dormant at night so it is a very rare occurrence for a bee to be out at that time. If an individual gets stung at night by a bee it is most likely due to the fact that they have accidently disturbed a bee’s hive. Bees live both above and below ground and are mainly active during the day. However, there are very few species that are considered to be “night fliers” and may sometimes become attracted to your porch lights.

Generally speaking for the most part, seeing a bee at night is not really something most people should worry about. If it is cold outside for instance, during the late evening, night, or very early morning bees usually tend to be less active as a result. You may see a few wondering around from time to time during later hours but they are usually not as aggressive and it is a rare happening that they will bother you in any way unless you annoy it by swatting at it or something along those lines. Bees are most active when the heat of the sun hits them during the day.

How Do Crabs Reproduce?

Crabs reproduce by laying eggs. When crabs reproduce they assume the doubler position. In this position the male crab carries the female. Mating between the two usually lasts for at least five and a half hours however the crabs maintain this position for up to three days afterward. The female crab then stores the male’s sperm on the underside of her abdomen where it will be used for two more spawning. These spawning occur within her three year lifespan.

The female crabs then migrate to slightly saltier waters after mating and attach between 100,000 to 2,000,000 eggs to the sperm stored under the abdomen. The crab incubation period lasts for about two weeks until the crab larvae hatch and is then released into the ocean to fend for themselves. The crab larvae will continue to grow for the next 40 days until they reach the adult crab stage.

During this time of growing, before they reach adulthood the crab larvae go through several molting stages. First they morph into what is known as the megalapore stage. This is the second larval stage and is characterized by a larger and thicker exoskeleton than the first larval stage. At this point the megalopae often resemble a cross between a crab and a lobster. The megalopae then can be found migrating to shore where they will then continue the next molting stage, after which they are classified as immature crabs or “first crabs”. This occurs about two months after the first larvae are hatched. These “first crabs” or immature crabs usually molt at least 18 times before reaching adulthood.

Crabs such as the hermit crab have been known to live for 30+ years. In captivity, they can even live long lives if cared for properly. Some crab owners have reported crabs living to be the age of 16 or so. Mating between hermit crabs occurs when a spermatophore is transferred by a male to the female as both crabs partially emerge from their shells. Depending on the size of the female, she can lay thousands of eggs and then deposit them with the aid of the gill grooming appendages on her pleopods along the left side of her abdomen. She then carries the eggs as they mature for about a month during which time the eggs will change from brick red to a dark gray color, as the embryos deplete their yolk supply.

The female hatches her eggs in the ocean by passing clusters of eggs from pleopods using her gill grooming appendages to her maxillipeds and forming clusters that are then passed to the tip of the claws and flung out to sea. The crab eggs immediately burst open upon contact with salt water and the new larval hatchlings known as the zoea float amongst the plankton. Each zoea will pass through 4 to 6 different stages that usually last anywhere from 40-60 days and follow the same metamorphosis as other crabs. Something to keep in mind if you are a crab owner is that although hermit crabs do mate in the wild if conditions are right, they will not breed in captivity. They only mate within their natural environments.

In very rare occurrences some crab enthusiasts that live in places like Southern Florida and have kept their pet hermit crabs in outdoor cages that are very large have been lucky enough to have several pregnant crabs from time to time. Unfortunately the zoeas did not survive.

Can Snails Breathe Underwater?

Aquatic and algae eating snails are of course able to breathe underwater as they reside here and breathe using their gills. Terrestrial snails such as your average garden snail however cannot breathe if placed under water and will most likely drown. I.e. not all snails are meant to live underwater. Aquatic snails on the other hand are very fast, active creatures when it comes to being in the water; however they are very slow creatures when on land. They will also die in about a week’s time if they do not have water.

Those snails that are designed with gills can often be found living at the bottom of ponds. Those that do not have gills and are in water will have to come to the surface often in order to breathe and it is for this reason that they often reside on the surface of the water.

Snails also have a thin skin that is permeable for water. On one hand this means that aquatic snails can also breathe through their skin. However it also means that they have to face the loss of water through their skin. These snails also breathe by using their gills (as mentioned above). These gills are located in the pallial cavity and resemble a double comb, with a stem and feathery protrusions that are responsible for the general process of gas exchange. Gas exchange is the absorption of oxygen from the water and the diffusion of carbon dioxide into the water. These gills are called cetenidia. Some species of snails are also designed with a secondary set of gills. These gills are located in the groove between the foot, mantle and shell.