Newts produce tetrodotoxin (TTX), a poison that targets sodium ion channels, for defense against their predators, garter snakes. Several species of garter snakes are resistant to newt TTX due to specific known amino acid substitutions in garter snake sodium channels. Which one of the following is best-suited to identify whether this adaptation in garter snakes has a single origin or multiple independent origins?
Show Hint
- Building a gene phylogeny of sodium ion channels in garter snakes
- Building a species phylogeny of garter snakes
- Building a gene phylogeny of newt sodium ion channels and species phylogeny of newts, and comparing them
- Building a gene phylogeny of garter snake sodium ion channels and a species phylogeny of garter snakes, and comparing them
The Correct Option is D
Solution and Explanation
To determine whether the adaptation to TTX in garter snakes is the result of a single origin or multiple independent origins, we need to compare the gene phylogeny of the sodium ion channels in garter snakes (which are involved in resistance) to the species phylogeny of garter snakes.
Step 2: Analyzing the options.
Option (A): Focuses only on the sodium ion channels in garter snakes, without considering their evolutionary history across species, making it less suitable for determining the origin of the adaptation.
Option (B): Builds only a species phylogeny of garter snakes but does not account for the genetic basis of the adaptation.
Option (C): Compares newt gene phylogeny with newt species phylogeny, which doesn’t help in identifying whether the adaptation in garter snakes has a single or multiple origins.
Option (D): Correctly suggests comparing the gene phylogeny of garter snake sodium ion channels to their species phylogeny, which helps identify whether the genetic adaptations occurred once or multiple times across species.
Final Answer: (D)
Top Questions on Evolution
The population of whirligig beetles in a lake grows or declines exponentially, i.e., \( N(t) = N(0)e^{rt} \), where \( N(t) \) is the population size at time \( t \), \( N(0) \) is the initial population size, and \( r \) is the per capita rate of population change, occurring only due to birth and death.
A researcher tracks population sizes for a year and finds the following:
Assuming that the individual birth rates remain constant throughout the year and only death rates are affected, which one or more of the following statements is/are true?
- Modern humans of European descent have a much higher proportion of Neanderthal DNA than modern humans of African descent. Which one or more of the following statements is/are consistent with this information?
From the table below, choose one or more of the options that match(es) the evolutionary biologists with the organisms they are well-known to have studied.
- A researcher wants to estimate the number of crickets in an isolated valley. They captured 56 crickets in the first session, and then marked and released them. In the second session, they captured 41 crickets of which 8 were already marked.
Assuming that there is no birth, death, immigration, or emigration in the cricket population during the study period, what is the estimated number of crickets in this valley? Match the appropriate population estimate with the data given. - Many insect species carry the endosymbiotic bacteria Wolbachia, which are maternally inherited. Wolbachia persist over time in these insect hosts by increasing the fitness of the infected host. This increased host fitness can lead to the fixation of Wolbachia in the host population, wherein all individuals carry it. Which one of the following statements describes a process that would NOT allow Wolbachia to become fixed in the host population?
Questions Asked in GATE EY exam
- An organization allows its employees to work independently on consultancy projects but charges an overhead on the consulting fee.
The overhead is 20% of the consulting fee if the fee is up to ₹5,00,000.
For higher fees, the overhead is ₹1,00,000 plus 10% of the amount by which the fee exceeds ₹5,00,000.
The government charges a Goods and Services Tax (GST) of 18% on the total amount (i.e., the consulting fee plus the overhead).
An employee of the organization charges this entire amount — that is, the consulting fee, overhead, and tax — to the client.
If the client cannot pay more than ₹10,00,000, what is the maximum consulting fee that the employee can charge? The table lists the top 5 nations according to the number of gold medals won in a tournament; also included are the number of silver and the bronze medals won by them. Based only on the data provided in the table, which one of the following statements is INCORRECT?
Eight students (P, Q, R, S, T, U, V, and W) are playing musical chairs. The figure indicates their order of position at the start of the game. They play the game by moving forward in a circle in the clockwise direction.
After the 1st round, the 4th student behind P leaves the game.
After the 2nd round, the 5th student behind Q leaves the game.
After the 3rd round, the 3rd student behind V leaves the game.
After the 4th round, the 4th student behind U leaves the game.
Who all are left in the game after the 4th round?
A stick of length one meter is broken at two locations at distances of \( b_1 \) and \( b_2 \) from the origin (0), as shown in the figure. Note that \( 0<b_1<b_2<1 \). Which one of the following is NOT a necessary condition for forming a triangle using the three pieces?
Note: All lengths are in meter. The figure shown is representative.
- Identify the option that has the most appropriate sequence such that a coherent paragraph is formed:
P: Over time, such adaptations lead to significant evolutionary changes with the potential to shape the development of new species.
Q: In natural world, organisms constantly adapt to their environments in response to challenges and opportunities.
R: This process of adaptation is driven by the principle of natural selection, where favorable traits increase an organism’s chances of survival and reproduction.
S: As environments change, organisms that can adapt their behavior, structure, and physiology to such changes are more likely to survive.