Anna Smirnova

To Master of arts and doctor of canon and civil law

Charles Robert Darwin

From student of Novosibirsk State University, Russia

Smirnova Anna

Dear Mr. Darwin,

I am writing to thank you for your last letter and tell you how much I'm interested in your views as well as in facts given by you.

The first edition of the main work of your life had appeared in our country a long time before I was born. However modern technologies allow to read and be fully imbued with your ideas. As mentioned earlier, our university has overcome all obstacles and achieved the impossible: thanks to the work of young researchers a real chance to choose you as a scientific advisor for the implementation of the thesis has appeared. Due to lack of time and opportunities for private conversation at the moment I send you a brief plan of the upcoming literature review with adjustments corresponding to real change for the period of your absence.

As already discussed, the basis for further research is formed on the most interesting from my point of view theses of the Chapter X "On the Geological Succession of Organic Beings " from your book "The Origin of Species". The research itself will consist in getting acquainted with new methods and also in visiting exhibitions of the Museum of Paleontology. The essence of this work is expounded in brief in the following paragraphs.

In your era the most of sedimentary rocks of the Earth were not yet been discovered and investigated, and paleontology was just forming. The invention of new methods of paleogeographic reconstruction allow us to examine the contents in the lowest known layers containing fossils more precisely. The ability of paleosols to accumulate and store information about long periods of existence, development and evolution of the natural environment is of particular importance.

In a modern paleogeography the methods of stable isotope geochemistry are widely applied. It is used the isotope variations of a number of elements - such as hydrogen, carbon, oxygen, sulfur, etc. The most common is the oxygen isotopic method. It can be a transparent method if its results are used for diagnosis of Palaeoclimatic events.

Paleomagnetic method allows to allocate isochronous levels, determine the time slices, which are the most suitable for a long-distance and global correlation of paleographic events. Methods of physicochemical analysis enable us to clearly identify the chronological boundaries of paleogeographic events with their time diagnosis and perform significant correlations regardless of the distance between the objects of comparative analysis.

The group of modern methods of absolute dating includes the potassium-argon method (K/Ar) based on the half-life of radioactive isotopes contained in volcanic rocks. This method is suitable for the dating of 1 million years and no more. Carbon method based on the content of radioactive carbon in the organic remains is used for dating from 100 thousand years or less. Thermoluminescent method is based on the estimation of the level of certain minerals glow during heating to 100-400 C, which is related to the duration of radioactive irradiation in natural conditions. This method is used for determining the age of 300 thousand years or less. Fluoride method based on the content of fluorine in the fossil bones due to its dependence on the assumed age of deposits is suitable for the dating of 1 million years.

Of particular importance are the methods of analysis of nuclear and mitochondrial DNA (deoxyribonucleic acid. DNA, dear Mr. Darwin - macromolecule (one of three major, the other two - RNA and proteins) that provides storage, transmission from generation to generation and implementation of the genetic program of development and functioning of living organisms. In mitochondrial DNA all mutations occurring in each generation are preserved, therefore mtDNA evolution is faster than nuclear DNA. Since the mutations have theoretically relatively constant speed, the number of mutations can be used for estimation of the time of occurrence and the future evolution of a given line . Nowadays the molecular clock method is widely used to refine the age of the most controversial fossil finds.

The most interesting thing is that all results of the applying the above methods can be seen themselves thanks to the method of three-dimensional reconstruction which is the process of obtaining the shape and appearance of real objects. More commonly used radiometric methods emit radiation to the object and then measure the reflected its part. Examples are moving light sources, the use of multi-colored lights, laser range finders and LIDAR, microwave and ultrasonic sensors and other methods of three-dimensional scanning. This allows to more accurately analyze the results.

The second part of my work will be devoted to the study of the facts about the discovery of intermediate and transitional forms that fill the gaps in the fossil chronicle.

Among the most prominent representatives there is coelacanth (latimeria chalumne). It is a living fossil fish which was discovered again after 70 million years. In 1938 a fisherman from a small village in the Comoros, near Madagascar, discovered a strange fish. The structure of this fish is unique and does not have any analogues in the animal world of the planet. Coelacanth skull is not continuous but it consists of two parts connected together by muscles. Instead of a solid backbone common to all vertebrates this fish has thick-walled elastic tube. Close relatives of coelacanths were the predecessors of all land animals.

A new discovery made by New Zealand paleontologists fills an important gap in the geologic history of pinnipeds. Recently the oldest known seal fossil was found in California. Until now we did not have fossil evidence of the first five million years of evolution of seals. The new discovery corrects this situation.

Paleontologists from the University of New South Wales found the remains of the largest marsupials, who could climb trees. Skeletons of animals were discovered in an Australian cave in 2010 year. In the cave there was found a large number of bones of these marsupials. The researchers found in total about 30 fossilized skeletons of nimbadons. Although previously nimbadons have been already found in Australia, the new discovery is unique in that animal bones are very well preserved. In addition, at this place there were found remains of nimbadons of all ages from young to elderly individuals.

Our information about the missing links are mostly fragmentary, but nevertheless the knowledge is constantly replenished with new discoveries and this area is an inexhaustible material for study and analysis.

I present you a thousand apologies for this obsessive and inexcusable long letter. But this is partly to blame for the friendly tone of your letter, my dear Mr. Darwin. If you have a lot of comments and have time to discuss the issue, I would like to meet with you this summer in London.

Once again, I would like to thank you for your time spent for my supervision. I highly appreciate this and hope that our collaboration will continue.

With great regards,

Anna Smirnova