Instructions

Read the following passage and answer the three questions that follow.

Considering the multitude of situations in which we humans use numerical information, life without numbers is inconceivable. But what was the benefit of numerical competence for our ancestors, before they became Homo sapiens? Why would animals crunch numbers in the first place? It turns out that processing numbers offers a significant benefit for survival, which is why this behavioural trait is present in many animal populations.

Several studies examining animals in their ecological environments suggest that representing number enhances an animal’s ability to exploit food sources, hunt prey, avoid predation, navigate in its habitat, and persist in social interactions. Before numerically competent animals evolved on the planet, single-celled microscopic bacteria — the oldest living organisms on earth — already exploited quantitative information. The way bacteria make a living is through their consumption of nutrients from their environment. Mostly, they grow and divide themselves to multiply. However, in recent years, microbiologists have discovered they also have a social life and are able to sense the presence or absence of other bacteria; in other words, they can sense the number of bacteria. Take, for example, the marine bacterium Vibrio fischeri. It has a special property that allows it to produce light through a process called bioluminescence, similar to how fireflies give off light. If these bacteria are in dilute water solutions (where they are alone), they make no light. But when they grow to a certain cell number of bacteria, all of them produce light simultaneously. Therefore, Vibrio fischeri can distinguish when they are alone and when they are together.

Somehow they have to communicate cell number, and it turns out they do this using a chemical language. They secrete communication molecules, and the concentration of these molecules in the water increases in proportion to the cell number. And when this molecule hits a certain amount, called a quorum, it tells the other bacteria how many neighbours there are, and all bacteria glow. This behaviour is called “quorum sensing”: The bacteria vote with signalling molecules, the vote gets counted, and if a certain threshold (the quorum) is reached, every bacterium responds. This behavior is not just an anomaly of Vibrio fischeri; all bacteria use this sort of quorum sensing to communicate their cell number in an indirect way via signalling molecules.

Question 41

Which of the following statements is NOT based on the premises of the passage?

Solution

The passage discusses the evolutionary significance of numerical competence in animals and bacteria for survival, emphasizing how processing numbers provides benefits in various aspects of life, such as exploiting food sources, hunting prey, avoiding predation, navigating in habitats, and engaging in social interactions. It specifically talks about how bacteria use numerical information (cell numbers) through a process called quorum sensing to coordinate their behaviour.

Option A appears to be more of a metaphorical statement about the collaborative effort required to achieve complex tasks than a statement about the practical application/benefits of numerical competence. Similarly, Option B is in line with the idea of using numerical information (the number of players on a team) to understand the advantage or disadvantage in a sports context; it reflects the concept of numerical competence, as discussed in the passage. Option C aligns with the passage's idea that representing numbers can enhance an entity's ability to influence or interact with others, in this case, politicians using numerical support to sway undecided voters. Option D matches with the idea in the passage - we are told that processing numbers offers benefits in social interactions: this statement corresponds to the idea that large numbers in protests can be a strategy to amplify voices and draw attention. Option E also aligns with the discussion - the concept of countries deploying forces in response to the numerical actions of other countries aligns with the broader theme of using numerical information for strategic decision-making, similar to how animals use numbers for survival.

Based on the above, we identify that Options B, C, D, and E are considered relevant because they are consistent with the passage's focus on the benefits of numerical competence in various contexts. Contrarily, it is unclear how Option A ties in with the idea that the passage is trying to convey.


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