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Gobiiformes is an order of fish containing about 210 genera and 1700 species. Gobies are marine fish which occasionally wander into adjacent freshwater areas. Their pelvic and medial fins unite and form a sucker, which they may use to adhere to objects such as plants and rocks. Some sand dwelling gobies have a symbiotic relationship with shrimp. The shrimp will dig a burrow in the soft sand substrate in which the two organisms live. The goby will then alert the shrimp to danger and they will both burrow deeper. There are also reef dwelling gobies. Some species of reef dwelling gobies exhibit a bidirectional sex change. Generally these go from female to male (protogynus), though under lab conditions the opposite direction has been induced by removing the female. When this occurs the largest male will become a female. If two males are ever placed in the same area, one will change to form a matching pair of male and female. Of course this may only work in lab conditions as in the wild, the gobies will likely simply migrate to a new area.

There is another form of parthogenesis used by fish in order to reproduce. This form is called hybridogenesis and is also used by monocha-lucida fish. During this process a diploid ML female will produce a haploid M egg. A haploid L sperm will join with the egg, though a female is always produced by this process. However once fully maturing as an adult, the paternal portion of the genes is discarded and the female will once again only produce haploid M eggs, and the cycle repeats.

Other fish use a variety of methods to attract their mates. For instance, some will have physical traits which monopolize on certain behaviors of the other sex. For example, many female fish carry their eggs in their mouths for safety, even before fertilization. Males of this species may produce structures on the ends of their fins which mimic the appearence of eggs. The female will therefore attempt to carry the mimic eggs in its mouth, at which time the male will fertilize the eggs already in the females mouth.

There are many reproductive strategies that fish use. For instance, many fish species reproduce through polygyny, where 1 male will have multiple partners. With this method, the female partners usually choose the territory, not the male. A male will determine and defend its territory and build nests which the females will visit or say in. This of course depends on how sutible the nest or territory is. Fish which are polyandrous have 1 female which reproduces with multiple males. An example of this is the anglerfish. The female in this species is very large. Males are tiny tadpole looking fish, which latch onto the female. Eventually these males become parasitic and literally fuse with the female, becoming a sort of male gonad on the female. This even goes so far as to share the same ciruclatory system. Whenever th female wants to reproduce, the male is signaled and sperm is released into the eggs, fertilizing them.

Some fish species reproduce through a method of parthenogenesis called gynogenesis, in which a female will produce an already fertilized and viable egg. This method may be observed in Poeciliopsis monocha and Poeciliopsis lucida. Normally there is a breeding population of diploid fish of each of these species. However, there is also a triploid population of female only monocha-lucida-lucida fish (MLL). These fish produce triploid MLL eggs. Oddly enough, even though there is no genetic transfer between egg and sperm, a diploid lucida sperm is still required in order to activate the MLL egg. Once activated, this egg will develop into a female MLL adult. The fish that comes from this egg is always a triploid female, a genetic clone of its mother and all the fish in its lineage before it.

There are some fish species which reproduce through parthenogensis. This may come in at least two froms, gynagenesis and hybridogenesis. One example of gynagenesis is with fish carrying monocha (M) and lucida (L) genes. Some females are triploid and carry MLL. These females will produce a triploid egg, also MLL. A diploid LL fish will release its L sperm in order to "fertilize" the MLL egg. There is actually no genetic transfer in this process, the sperm only stimulates the MLL egg. Once successfully stimulate, the egg activates and a new triploid MLL female (yes always female) fish is born. So where do males come from if all that is produced from this process is females? The normal diploid population, which is favored by diploid males. Therefore, there are two seperate populations. A diploid population of both males and females and a triploid population of all MLL female clones.

Rivulus, a genus of freshwater fish, has a very odd reproductive strategy. This fish is hermaphroditic, which in itself it not too uncommon among fishes. Rivulus is able to self fertilize, though not in the way that a majority of self fertilizing fish do. Most fish which reproduce by this method are females which produce fertilized eggs, more or less producing clones of itself. The drawback to the strategy is it limits genetic diversity. The rivulus however, will produce both sperm and eggs. When gametes are formed during meisos, Rivulus will therefore maintain the "crossing-over" phase which most other hermaphorditic fish lack. This gives the fish the ability to maintain some level of genetic diversity among its populations. Of course this diversity is still limited by the fact that there isn't multiple populations mixing.

The order Lampriformes is largely catagorized by morphological features. Fishes in this order have a Mesethmoid bone posterior to their lateral ethmoids, an elongated premaxilla, their first dorsal pterygiphore insterts anterior to their first neural spine and have the absence of a platine prong. Oarfish, Lampris and apahs are all examples of Lampriformes. The giant orfish, of the family Regalecidae is known as the king of the herrings. This fish is a very elongate and slab sided. The giant oarfish has a tube shaped mouth, which it uses to suck in its prey. Furthermore it has a very large eye and red fins. The most notable feature of the Giant Oarfish is its crownlike spines on the top of its head, which are fused with its dorsal fin and follows the entire length of its body. The Giant Oarfish is a very large fish and can reach up to 11 meters in length. Its body stays ridgid as it swims, but sends sin waves down its long dorsal fin to propell itself. There is a notable absence of scales on the oarfish as well.

Georges bank is a region of ocean just south of the Gulf of Maine and East of cape cod Massachusetts. This region is only 45 meters deep, allowing sunlight to reach the bottom making it very nutrient reach. Furthermore, the gulf stream and Labrador current intersect here, bringing their own nutrients and “mixing it up.” The cold water makes it perfect for the Atlantic cod and a variety of other fish species. Due to this large productivity, Georges Banks has been an important economic fishing zone. Unfortunately overfishing over the last hundreds of years has decreased the biomass of this area by nearly 90%. 66% of this decline has occurred in the last 50 years alone. Unfortunately this does not seem to be changing, despite attempts of (admittedly insufficient) regulation. Recent fears of global warming seem to be effecting the gulf of Maine significantly. Unfortunately the fish here are adjusted to live in the cold waters, and as water temperature rises it will only get harder for them to survive here. Not only is the loss of fish species tragic on its own, but we as humans rely on this area for food and money.

The family Gadidae contains fish such as the cod and haddock. There are 24 species of fish in this family. All of the Gadidae are marine dwelling fishes, with the exception of the Lota lota which lives in freshwater. This family is united by several characteristics. These fish have a single chin barble, three dorsal fins, two anal fins, and a diphycercal tail. Their pelvic fin is anterior to their pectoral fin, located along the same axis and close to their rostral end.

The Atlantic cod is a very notable species of Gadidae. These are a very R-Selected fish and females of about 5kg will lay 9 million eggs, though the amount will vary depending on the size of the fish. Cod are relatively long lived and live to be about 25 years of age. They are predators and will eat both other fish and invertebrates. Due to their low red muscle and high white muscle content, Cod are the perfect food fish. Their high presence in the north eastern united states have made them an economic staple. Unfortunately commercial fishing has diminished their populations drastically. Unfortunately global warming is making it more difficult for Cod to reproduce and further diminishing populations. Generally  Atlantic Cod only like to reproduce in waters colder than 12C, so even a tiny shift in temperature can have a drastic impact on their survival.

While the closure of a Mimosa pudica plant serves as a defense mechanism against predators, it also comes at a drawback. In this state, the leaves of the plant cannot collect as much sunlight, therefore limiting its ability to photosynthesize. There has been research done to test the effects of light availability in relation to the closure time of Mimosa pudica, and it is likely the plant adjusts its closure time to depending on light availability. There is also evidence supporting that the health and state of a plant, and not the individual leaves on the plant vary the closure time in response to touch. Thus, the conditions a Mimosa pudica is grown under may affect its response rate and overall closure time.