Misconception in Understanding Evolution

[Theertha (Theertha M.D.)]

Misconception in understanding evolution

How can we define Evolution !!

I thought evolution is what lamarck described in its theory.

Use and disuse of an organ leads to the change in its shape later that was acquired by next generation .Like short neck girafee changes to long neck girafee.

Later on CUBE Chatshaala discussion i understood that what a wrong concept that i was having about evolution .

Later i found the same issue with @Shraddha276 @Smiti ⁩ ,not an issue but some of us understood evolution in that way .

We started discussion with how darwin finches changes its beak shape ??

In yesterday’s chatshala discussion we tried to found out our misconception regarding evolution .

1) First confusion was that based on the food a bird can choose to change the shape of beak
2) Second was that not only the shape of the beak can be changed based on the choice, but also once such shape is chosen that shape gets inherited in the next generation

Then we understood that probably a mutation is occuring, that is leading to the variations among finches .

Later we came across how mutation is happening !!!

Later on discussion @⁨shalinisharma⁩ made a great attempt regarding how mutation in beta chain of heamoglobin leads to Sickel shaped RBC.

Following Summary written by Shalini

We started our discussion with Beta chain of Hb and wanted to know from where this beta has came in the story of sickle cell anemia.
So our Hb protein is composed of 2 chains of alpha and beta each.
What is this alpha and beta chain?
It is a polypeptide chain of amino acid which differs in the sequence of amino acid.

What does mean by polypeptide?

What is happening to Hb protein when there is valine (Val) instead of glutamic acid (Glu)? What is causing the RBC to become sickle shaped?

Then, we discussed about the structure of both the amino acids. (Glu) is a polar amino acid while (Val) is non-polar amino acid. there is change in polarity of amino acid which is causing structural change that is not allowing the alpha and beta chains to arranged in prope structure as it before.

Now, how does amino acids link (peptide linkage) to each other what chemical reaction takes place? And when we call dipeptide (two amino acids linked by one peptide bond), tripeptide (3 aa , 2 peptide bond), and so on.

@Smiti @Shraddha276 @shalini @sakshiconsultant2002 & others

[Arunan]

Where are we now on Gaps & Misconceptions regarding Evolution? @Theertha

[kvk (Vinod Kumar K)]

Molecular evidence suggests that between 8 and 4 million years ago, first the gorillas, and then the chimpanzees (genus Pan ) split off from the line leading to the humans. Human DNA is approximately 98.4% identical to that of chimpanzees when comparing single nucleotide polymorphisms… Human evolution - wikipedia. The chimp tribe would not have changed 1.6% of its DNA and split off to form the human tribe. One singular chimp must have changed, say 0.01 %, of its DNA to that in the current human DNA. How did this Adam (?!) manage to create the human tribe with the new 0.01% human DNA?

[kvk (Vinod Kumar K)]

My friend suggests that I read Speciation: The Origin of New Species. a Nature Education lesson

[Chitralekha (P. Chitralekha)]

I do not think humans evolved from chimps, not even that one single chimp. There must have been the ancestors (more like the apes or Orangutangs, if I am not mistaken) from which chimps and humans, and may be even gorillas, evolved in different directions.

Chitralekha

[akshay (Akshay S Dinesh)]

Along with speciation, it will be interesting to look at hybrids like Liger, Tigon.

Makes one think about Humanzees and then “what does it really mean that humans are a different species?”

[AGodForTheAtheist (james)]

I am more interested in exactly what we are and how we began as a consciousness. The rest is simple
“ think I have Quantum Physics- pretty much figured out. It is really quite simple.
Wave - consciousness (waves)
Particle- subatomic electromagnetic energy(waves)
Quantum- where waves join to create the physical perception of reality by vibrating and defining those various frequencies to create this more enjoyable existence as a singularity consciousness (1) in a universe of nothingness (0) vibrating and creating everything you can imagine exists. 100110011 a computer recognizes this language- but the consciousness creates a more enjoyable experience by vibrating and creating sounds colours and ideas . ”

[kvk (Vinod Kumar K)]

ok humans have not evolved from chimp but both humans and chimps appear to have split off from an ancestor species. Wikipedia says 98.4 % of human DNA is similar to that of chimpanzee. So both chimp and human have 98.4% of their DNA from the ancestor species and 1.6% differ. Let us not worry about how the 1.6% of the human DNA differ from that of chimpanzee; let us look at how the 1.6 % of human DNA differs from that of ancestor. How close the human DNA is to its ancestor and how this change occurred? The 1.6% different direction from the ancestor can only be an accumulation of several small changes (say 0.0001% change by Adam1) by several singular ancestors over millions of years?

[kvk (Vinod Kumar K)]

Humans and chimpanzees shared a common ancestor approximately 5-7 million years ago (Mya). The difference between the two genomes is actually not approximately 1%, but approximately 4%–comprising approximately 35 million single nucleotide differences and approximately 90 Mb of insertions and deletions Comparing the human and chimpanzee genomes: searching for needles in a haystack. Ajit Varki, Tasha K Altheide

[Chitralekha (P. Chitralekha)]

Wikipedia says 98.4% of human DNA identical to that of chimpanzees because of shared/common ancestor. That 1.6% difference is because of mutations in human and chimpanzee DNA as they evolved separately from the ancestral group. Many of the ancestral genera and species of Homo which arose during the process of human evolution became extinct leaving out Homo sapiens (which may have had a survival advantage).

[kvk (Vinod Kumar K)]

Forget about the 1.6 % difference between human and chimp DNA. Assuming a common ancestor, say humanChimpGreatGranpa, we say that human DNA differs, say 1.12% from that of humanChimpGreatGranpa. How did this change come about? A grand old humanChimpGreatGranpa hc1 might have created about 0.01% new DNA and passed it on to her kids. How can this 0.01% new DNA find its way to all of humans today? The same question can be asked about all the other DNA changes that occurred to many hcn finally summing upto 1.12% today.