The spengler’s freshwater mussel is an specie of freshwater bivalve mollusk that it currently only known scientifically confirmed the presence of populations living in the Ebro basin. Is originally from the big atlantic and mediterranean rivers from occidental Europe and North Africa.

It is a mollusk in the shape of a clam, that is, is a bivalve. It grows to 20 inches, live up to 80 years and lives in fresh water. It has a extremelly thick and heavy shell,blackish, looking Curb as an human ear.

The little amount of spengler’s freshwater mussel is found actually distributed in channels with clean water forming isolated colonies located in shallow beaches with gravel bottom consolidated and well ventilated. Its natural habitat is the funding of gravel, mud, sand, silt and stones, where itlives half-burried. Formerly major banks was shallow and also accumulates in deep pools of rivers by the drag characteristic of the dynamics of river.

Specifically malacologists only aware of the presence of this species in the province of Zaragoza and Tarragona.
In Zaragoza are known colonies in the Imperial Channel( where there are more or less two thousand of them). In Tauste Channel and in the area of Sastago in the Ebro river, without quantifying. In Tarragona there are know colonies in the final stretch of the Ebro.

The species can not be played since before 1970 and has over 30 years waiting for their own extinction. The fertility of the spengler’s freshwater mussel is huge. So, why it can not reproduce? This species of mollusk is multiplied by a larvae-called glochidia, which discharged into the river water. But the complexity of the reproduction of the nymph is that the larvae can only develop if they remain a part of their life cycle entrenched within the guts of a small number of fish species. One is the Atlantic sturgeon disappeared from the waters of Ebro does exactly the same time he has not played the Naiad. The other species is the pitch blenny monk, who is on the verge of extinction due to pollution of water and sand and gravel extraction of funds from the Ebro River.


I have been searching for a web site in wich there is explained exactly what we saw the other day, but I dont found it, so I think that this is also a good and interesting web page to learn about ecology.

On the video of the theory of natural selection the teacher talks about Darwin and his theory.

Darwing started thinking about two circustances, the favour variations who want to be preserved, and the unfavour variations who want to be destroyed, this led to the theory of natural selection. Firstly, he wrotte but didn´t publish his theory of natural selection.

Also Darwin though about artificial selection, there are a lot of examples about it, for example horses, cows, fishes… By artificial selection we can have cabbages, couliflower, rapeseed, turnips or brocoli from a white mustard plant.

Now we are going to see the important years of the theory of Darwin:

1844- Darwin started to study a lot of biology from books, specially he studied burnacles, he spent 8 years studing burnacles. He wanted to study them bebore publising his theory of natural selection.

1856- He wanted to make sure his theory, so nobody could argue with him. So he started thinking in overpopulation. Finally Darwin was convinced by his friends to give out his theory.

1858- Darwin appeared before The Linnaean society and propose the theory of natural selection.

1859- The controversial book called Origin of species was published.

1871- In this year Darwin publish another book, more controversial than the last one, called The origin of man.

Darwin said one of the most simplest, elegant and important theories, that was the theory of natural selection, that consist on 5 points:

1) Overpopulation: more organisms are born than can posibly survive.

2) Variation.

3) Competition: organisms would compete for everything.

4) Fittest will survive.

5) Reproduction.

Finally the teacher say that all of this traits will be passed to the next generation.

The jaguar is a compact and well-muscled animal. There are significant variations in size: weights are normally in the range of 56–96 kilograms. Larger males have been recorded at 159 kilograms, and smaller ones have extremely low weights of 36 kilograms. Females are typically 10–20% smaller than males.

Adaptation features:

  • A short and stocky limb structure makes the jaguar adept at climbing, crawling and swimming.
  • The head is robust and the jaw extremely powerful. It has been suggested that the jaguar has the strongest bite of all felids, and the second strongest of all mammals; this strength is an adaptation that allows the jaguar to pierce turtle shells.
  • A comparative study of bite force adjusted for body size ranked it as the top felid, alongside the clouded leopard and ahead of the lion and tiger.
  • The jaguar hunts wild animals weighing up to 300 kilograms in dense jungle, and its short and sturdy physique is thus an adaptation to its prey and environment.
  • The cat is covered in rossetes for camouflage in its jungle habitat.
  • While the jaguar employs the deep-throat bite-and-suffocation technique typical among Panthera, it prefers a killing method unique amongst cats: it pierces directly through the temporal bones of the skull between the ears of prey (especially the capybara) with its canine teeth, piercing the brain.

File:Jaguar sitting.jpg

A six percent of the population of jaguars in South America have a condition known as melanism. The melanistic form is less common than the spotted form and is the result of a dominant allele. Jaguars with melanism appear entirely black, although their spots are still visible on close examination. Melanistic Jaguars are informally known as black phanter, but do not form a separate species. Rare albino individuals, sometimes called white panthers, occur among jaguars, as with the other big cats.

File:Black jaguar.jpg

Over-production: The gestation period lasts 93–105 days; females give birth to up to four cubs, and most commonly to two.The young are born blind, gaining sight after two weeks. Cubs are weaned at three months but remain in the birth den for six months before leaving to accompany their mother on hunts. They will continue in their mother’s company for one to two years.

Struggle for existence: The jaguar is an obligate carnivore, feeding only on meat. It is an opportunistic hunter and its diet encompasses 87 species.

Variation: They have very significant variation in size, tending to increase from the north to south. The base coat of the jaguar is generally a tawny yellow, but can range to reddish-brown and black. The cat is covered in rosettes for camouflage in its jungle habitat. The spots vary over individual coats and between individual Jaguars. Also melanism and alvinism can occur in jaguars.

Survival of the fittest: Jaguars that have better skin to camuflate, hunt better.

Advantageous characteristics are passed on to offspring: (I dont know what to put on this)

What is DNA fingerprinting?

The only difference between peopl or animal is the order of the base pairs, because the chemical structure of everyone´s  DNA is the same. There are so many millions of base pairs in each person’s DNA, so every person has a different sequence.

Using these sequences, every person could be identified by the sequence of their base pairs. However, it would cost a lot of time because there are so many millions of base pairs. Instead, scientists are able to use a shorter method, because of repeating patterns in DNA.

These patterns do not, however, give an individual “fingerprint,” but they are able to determine whether two DNA samples are from the same person, related people, or non-related people. Scientists use a small number of sequences of DNA that are known to vary among individuals a great deal, and analyze those to get a certain probability of a match.

what are the aplications for DNA structure?

1. Paternity and Maternity 
People inherit them VNTRs from them parents, VNTR patterns can be used to establish paternity and maternity. The patterns are so specific that a parental VNTR pattern can be reconstructed even if only the children’s VNTR patterns are known. Parent-child VNTR pattern analysis has been used to solve standard father-identification cases as well as more complicated cases of confirming legal nationality and, in instances of adoption, biological parenthood.

2. Criminal Identification and Forensics
DNA isolated from blood, hair, skin cells, or other genetic evidence left at the scene of a crime can be compared, through VNTR patterns, with the DNA of a criminal suspect to determine guilt or innocence. VNTR patterns are also useful in establishing the identity of a homicide victim, either from DNA found as evidence or from the body itself.

3. Personal Identification
The notion of using DNA fingerprints as a sort of genetic bar code to identify individuals has been discussed, but this is not likely to happen anytime in the foreseeable future. The technology required to isolate, keep on file, and then analyze millions of very specified VNTR patterns is both expensive and impractical. Social security numbers, picture ID, and other more mundane methods are much more likely to remain the prevalent ways to establish personal identification.

What are the problems of DNA fingerprinting?

Nothing about DNA fingerprinting is 100% assured. The term DNA fingerprint is, in one sense, a misnomer: it implies that, like a fingerprint, the VNTR pattern for a given person is utterly and completely unique to that person. Actually, all that a VNTR pattern can do is present a probability that the person in question is indeed the person to whom the VNTR pattern belongs. Given, that probability might be 1 in 20 billion, which would indicate that the person can be reasonably matched with the DNA fingerprint; then again, that probability might only be 1 in 20, leaving a large amount of doubt regarding the specific identity of the VNTR pattern’s owner.

 What is electrophorosis?

Electrophoresis is the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric field. This electrokinetic phenomenon was observed for the first time in 1807 by Reuss, who noticed that the application of a constant electric field caused clay particles dispersed in water to migrate. It is ultimately caused by the presence of a charged interface between the particle surface and the surrounding fluid.

Griselda Pascual was born on 1926 in Barcelona. She had a doctorate in mathematics and she was algebra lectured of the University of Barcelona. In 1950 she was institute professor in Tortosa, later in the Maragall institute of Barcelona, when the city only had twelve institutes, developing there one of its main areas of work: the teaching of mathematics. She has CSIC scholarship and then with a Von Humbold scholarship, she studied diferential geometry in Freiburg (Germany),  theory of groups and lattice and she started her works about plane’s and sphere’s mosaics. On her return, she participed in the work devoted to the education reform of baccalaureate and fought to introduce in it the so-called mothern mathematic. Along three years she was director of the maragall high school of Barcelona. In 1974 she had a doctorate about Numbers Theory. After her retirement, she finished the traduction, fom latin to catalan, of the Aritmetic Disquisitions of Gaus, published by the Catalan Studies’ high school (1996) in edition facsímil.