Fiddler crabs live through the Pacific Ocean, South Atlantic Ocean and the Mediterranean on land (McLain 2010). There are over 100 species and their size ranges from 2.5 to 5 cm wide (McLain 2010). Both of the female claws are small but one of the males claw grows significantly larger and it can weigh up to half their bodies weigh (Murai 2009). Adults will continue to grow by molting as they age (McLain 2010). The male will use his overgrown claw as a status of strength and health but some male fiddler crabs can fake a large claw and still get the same benefits even though he is actually weak (Murai 2009).
The size of the male claw varies according to how much nutrients and foods are in his habitat and how much he is able to eat (McLain 2010). Fiddler crab diet consist or algae, bacteria, decaying plants and, animal matter, and fungus (McLain 2010). They try to eat in puddles of water so it is easier to separate food from dirt (McLain 2010). The female crab uses both claws to feed while the male can only use his small claw making it harder to feed (McLain 2010). The male crabs will fight over territory for resources (McLain 2010).
Before males fight they exhibit their big claw and if neither one backs away they will fight (Hirose 2010). In most fights they wrestle around for show and rarely get hurt (Hirose 2010). If they happen to lose their big claw during a fight or its lost to a predator the small claw will begin to grow while the other is regenerated (Murai 2009). The new claw will grow to be just like the old one, but some males can manipulate its growth and grow a new claw that looks like the original but uses less nutrients to produce because its lighter and toothless (Murai 2009). This fake claw is we...
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...w or they just can’t find large portions of food to grow back or support a big claw (McLain 2010). The females are attracted to healthy big claw males (Muramatsu 2001).According to natural selection the males unable to have a healthy life will not reproduce (Muramatsu 2001). Some of these crabs that have a tough time will get so desperate to be successful they will grow a fake claw that cost less resources to grow/maintain and looks exactly the same as a normal one with the exception that its lighter, has no teeth and its weaker (McLain 2010). Neither males nor females will know the difference (Murai 2009). The other males will respect him for having a stronger claw and the females will be attracted to him for having a better wave/mating ritual (Murai 2009). These crabs cheat natural selection by faking superiority making natural selection irrelevant (Murai 2009).
T. californicus is found from Alaska to Baja in small, shallow tidepools and tidal flats in the upper spray zone where they cannot avoid the full effect of visible and ultraviolet (UV) radiation. Individuals assemble in areas of lower radiation at midday, yet have no preference to the intensity of light at dawn and dusk (Hartline and Macmillan 1995). These tiny arthropods inhabit all types of marine sediments from sand to fine mud and ooze. Along with plankton, T. californicus eats microscopic algae, protists, bacteria, diatoms, algae and microbes (McGroarty 1958). When the concentrations of the species in their habitats are high, T. californicus will turn to cannibalism for a food source. The nautilus eye present in the species is rich with fatty acids and provides a good food source for the animal.
A lobster must shed its shell in order to grow. It takes about five to seven years for a lobster to become a legal size harvestable adult. Soft-shell is the term used for a newly molted lobster. A soft-shell lobster has a shell with room for growth. Soft-shell lobsters are not as full of meat because their new shell is larger than the muscle inside the body. The part not filled with its body’s muscle tissue is filled with water. Soft-shell lobsters may look big on the outside, but they have a much lower meat yield on the inside. Most adult lobsters molt from June to September depending upon location and water temperatures.
The yeti crab is a very recent discovery. Nothing is known about its reproduction habits, due to its place of living.
The picture above shows the vast difference that there can be in animals, to the right is Emerita Analoga (sand crab), and to the left is Zalophus Californianus (California Sea Lion). The sand crab is an invertebrate while the seal is a vertebrate and mammal. Invertebrates make up 90% of all an...
The barnacles not only live and reproduce inside the host crab, but they control it. The tendrils attached to the nerves produce substances that change the crab’s endocrine system. This leads to the crab’s body absorbing its own Y-organ. The Y-organ instructs the crab to molt or grow. The crab’s androgenic gland is also degenerated. The androgenic gland controls sex differentiation. At this point, the crab is unable to grow, molt, regenerate lost limbs and it is infertile. When the barnacle inhabits a male crab, the changes feminize him. The male crab will resemble and act like a female. He may even perform a female mating dance. After all this has taken place, the host crab will take care of the parasitic eggs. The crab acts as if the eggs are its own. At the right time, the crab will climb up onto a high rock, and tend to the egg pouch, as it would do in its own reproductive cycle. When the generous number of eggs are ready to hatch, the crab will bob up and down in the water to release them. The crab will then mix the floating eggs with it’s claw to set them on their way. These larvae will usually find new hosts, which continues this
If someone is a native of Maryland, they know exactly what one is talking about when the Maryland Blue Crab is brought up into a discussion. In 1989, the Maryland Blue Crab, scientifically known as the Callinectes sapidus Rathbun, was designated the State Crustacean (Blue Crab, Maryland State Crustacean). This crab is not only a key component on the ecological system of the Chesapeake Bay, but also a key economical component of commercial fisheries; although not endangered, the issue of maintaining the population of the species is critical to the Chesapeake Bay and also its inhabitants.
Imagine a creature that has a skeleton on the outside of its body, that has eyes that protrude on stalks, and whose blood doesn't flow through blood vessels but, instead, pools and surrounds body tissues. What is this monstrous creature? What if I were to tell you this isn't a monster, but something you've probably seen and maybe even eaten?! Yep, this strange creature is a __crustacean__! There are over 50,000 species of crustacean and they come in all shapes and sizes, from an ocean-dwelling crab to an immobile barnacle! But before we delve into the types of crustaceans, let's take a moment to go over the characteristics and anatomy they share.
The Dwarf Seahorse mostly eats non insect arthropods and is always a carnivore. To catch food they hook onto seagrass and are well camouflaged and catch drifting tiny animals like brine shrimp, copepods, and freshly hatched shrimp larvae. They prey is sucked near through the snout. Food progress in the seahorse is very fast causing it to absorb little nutrients. Because of this the sea horse can consume up to 3,000 brine shrimp a day (Animal Diversity Web).
and charge with their spines. They have no known predators in the region so their population can
There are some animals that just have strong muscles that help them carry out their daily lives. The big cat family is one family of predators that knows how to use these...
good source of food. The Trilobites fought back for a time, growing spines during the
To start off, the horseshoe crab lived 200 million years before dinosaurs. What’s astounding is that while dinosaurs have become extinct, the horseshoe crab is still alive and well today (Horseshoe Crab:Saint Louis Zoo). Next is that it might not seem like it, but this critter is actually a predator. The crab likes to feed on things such as small clams, crustaceans, worms, algae, and other animals (Steel). Furthermore this animal is also known as the king crab. Finally the male horseshoe crab is actually shorter than the female the crab. The male is about 14-15 inches long from head to tail, while the female is measures in to be 18-19 inches long (Horseshoe Crab
For male cats, they have a penis, prostate, scrotum (with paired testes), which all aid in creating sperm and testosterone. Additionally, the most unique feature they have is that on their penis they have little spins and barbs that hold the penis in during ejaculation.
Crustacea is a large subphylum of Arthropoda, consisting of almost 52 000 described species, including animals like crabs, lobsters, shrimp and barnacles. The majority of these are aquatic, living in marine or fresh water environments, though some have adapted to living on land like some crabs and woodlice. Most crustaceans are relatively small, though there are some exceptions. All of them have a hard, strong exoskeleton, divided into two parts, which has to be shed in order to allow the animal itself to grow. They have a large circulation system, where blood is pumped around the body by the heart. Only some crustaceans have sexes separate, and those that are usually mate seasonally and lay eggs. The study of Crustacea is called carcinology.