Given below are two statements:
Statement I: Similarities in proteins and genes performing a given function among diverse organisms give clues to common ancestry.
Statement II: The embryological support for evolution proposed by Ernst Heckel was approved on careful study performed by Karl Ernst von Baer.
In the light of the above statements, choose the most appropriate answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Statement I is true but Statement II is false
NCERT gives several kinds of evidence for evolution, such as fossils, comparative anatomy, biochemical similarities and an embryological proposal that was later rejected.
Statement I: Similarities in proteins and genes performing a given function among diverse organisms give clues to common ancestry. — True. When diverse organisms carry similar proteins and genes for the same function, they point to the same shared ancestry, just as structural similarities do.
Statement II: The embryological support for evolution proposed by Ernst Heckel was approved on careful study performed by Karl Ernst von Baer. — False. Heckel based his proposal on features, such as a row of vestigial gill slits, seen in the embryos of all vertebrates. Von Baer studied this carefully and disapproved it, because he noted that embryos never pass through the adult stages of other animals.
NCERT Extract:
What are the Evidences for Evolution? – “… Embryological support for evolution was also proposed by Ernst Heckel based upon the observation of certain features during embryonic stage common to all vertebrates that are absent in adult. … However, this proposal was disapproved on careful study performed by Karl Ernst von Baer. He noted that embryos never pass through the adult stages of other animals.”
What are the Evidences for Evolution? – “In the same line of argument, similarities in proteins and genes performing a given function among diverse organisms give clues to common ancestry. These biochemical similarities point to the same shared ancestry as structural similarities among diverse organisms.”