The Treaty of Tordesillas only specified the line of demarcation in leagues from the Cape Verde Islands. It did not specify the line in degrees, nor did it identify the specific island or the specific length of its league.
Watson-Crick has discovered the current-structure of DNA in 1953.The famous double-helix structure of DNA has its own significance. There are basically four nucleotide bases, which make up the DNA. Adenine (A), Guanine (G), Thymine (T) and Cytosine(C).
1 1920 - Chromosomes are proposed as the mechanism by which inherited characteristics are passed on. 2  1944 - DNA is first connected to the inheritance of traits. 3  1951 - The first sharp X-ray diffraction photographs of DNA are obtained. 4  1953 - Crick and Watson describe the structure of DNA. 5  1956 - DNA is made artificially.