The story of a butterfly that explains how species evolve.

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People often wonder or rather doubt how new species are formed. Some people doubt the whole phenomenon of evolution because it's "a theory of evolution". However, in reality, evolution happens and we can find evidence of it in nature. Here, for instance, a species of butterfly in Amazon region was found to have evolved from the hybridization of two other species of butterflies. Interestingly, the descendants of all these three lineages of butterflies coexist in same geographical region and two of these occasionally mate with each other.
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EDTA

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EDTA: Ethylenediaminetetraacetic acid

This comes as disodium salt dihydrate.




First time I tried to make it during by degree education, I just weighed the appropriate amount and tried dissolving it in water by shaking the flask. After failing, I asked some of my seniors who were pursuing their PhD then. I seldom used internet those days. For those who aren't ignorant as I was,  here is how I make the EDTA solution.

  • Weigh the appropriate amount of EDTA in a flask.
  • If you are preparing 100 ml of total volume of the solution, add 70 ml water. 
  • Take some ice in a beaker or ice-bucket and place the flask in this.
  • Add one sodium hydroxide (NaOH) pellet and shake the flask intermittently putting it on ice to prevent heating.
  • If NaOH pellet is dissolved completely and EDTA still remains undissolved, add another pellet.
  • Keep on adding one pellet at a time until all of the EDTA is dissolved.
  • Adjust volume to 100 ml (or whatever volume you are making).

The Sigma product information tells that 0.5 M EDTA at pH 8.5 is stable at 4 degree Celsius for months. Also, this solution can be autoclaved.

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