Read the text above. For each question (1–6), choose the sentence (A–H) that best fits the gap. There are two sentences that you do not need. Mark your answer on the answer sheet. There is an example at the beginning (0→I).
Strength vs Brains
Is there any nature scene more iconic than a ram crashing down upon his rival with huge, curving horns that can weigh 15 kg apiece? (0) Have you ever felt awe upon seeing the whopping, two-metre-long antlers of a fully grown bull moose? Humans have been fascinated by such animals for longer than anyone can remember. Some of the oldest art ever found depicts the horns of an ancient buffalo and the tusks of a boar, painted on the walls of caves ages ago. (1)
. A study published in the journal Behavioural Ecology and Socio-Biology provides the first evidence that, as male mammals evolve larger, elaborate antlers and horns used as weapons for combat or signals of their fitness, the females of those species develop larger brains than expected.
"I think that the females are an important aspect of biology that often gets overlooked", says Julia Lopez, a socio-biologist and lead author of the study, "because visually they appear dull, usually not as elaborate as males". (2)
. And it may change what experts think about how much decisionmaking ability they display when choosing a male.
"It's not that as males invest more in their weapons, they become less smart", clarifies Lopez. (3)
. Rather, male brain sizes appear to stay the same even as evolution appears to select ever larger headgear. At the same time, females seem to pour resources into brain size. And while it remains unclear if these traits are directly linked, which would tell us a lot more, the study shows that they do indeed correlate.
To dig deeper into the quality of the correlations, the authors of the study embarked on a quest in various museums to examine available specimens. (4)
. What might be happening is that males are investing more in their horns to make them more appealing signals for the females. This adds complexity to their social system. (5)
. Measurements of the skulls, brain volume, and horn sizes of some 400 specimens from 29 different species of deer, moose, goats, sheep and antelopes stand in support of this.
Evolutionary biologists, as independent experts, admit the study has enormous implications, but note several limitations. For instance, brain size does not necessarily translate to intelligence. (6)
. While applauding the authors for examining as many specimens as they did, they maintain that their sample represents only a fraction of the weaponed hoofed animals on Earth. Who knows if the pattern might change when other antlered, horned, or tusked species are evaluated?
"Be that it as it may, the prevailing story has long been that the most powerful males get the females. But it might just be that females do make a reasoned decision rather than an instinctive one, when choosing their partner", says Lopez.
6 bodova
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