> African fish is fastest-maturing vertebrate
What it is : Scientists have found out that the African turquoise killifish reach sexual maturation faster than any other vertebrate -- in just 17 days.
This east African killifish live in temporary puddles created during seasonal rainfall. Their survival depends on being able to reproduce in very short amounts of time, and for the first time scientists have discovered how they do this -- by growing up to 23 per cent of their body length in a single day and starting to reproduce at as early as 17 days old!
The eggs laid can hatch after just about 15 days, making the time between two successive generations just about a month.
This is important because the fish’s habitat usually dries out in 3-4 weeks. In case the puddles dries up before eggs hatch, the embryo can stay dormant for a few months till the next rains come.
Why it matters : The life cycle of the turquoise killifish show how animals adapt to extreme conditions by developing extreme lifespans, in this case with explosive growth, rapid sexual maturation and high reproduction rates. The more insight we have into lifestyles of extremophiles the more we learn about whether life could be possible in harsh and strange conditions.
> Monkey's alarm calls reveal predator location
What it is : The alarm calls of a species of monkey called black-fronted titi were deciphered by researchers to be much more complex than thought.
Some 40 million years back, monkeys split into two lineages -- New World and Old World monkeys. The black-fronted titi from Brazil is a kind of New World monkey.
Researchers used different kinds of predators -- a bird of prey called caracara and a cat called oncilla -- in different locations and observed the kind of alarm call that they induced in the titis.
They found that based on the type and location of the predator, the titi used different combinations of two different calls (‘A call’ with a rising pitch and ‘B call’ with a falling pitch).
It was known that Old World monkeys combined different kinds of calls to convey different meanings. But this is the first time a New World monkey has shown evidence of having a primitive syntax, and also the first time a non-human primate has been found to express both type and location of predator through their calls.
Why it matters : This discovery suggests that simple syntactic rules may have developed before the Old World-New World split happened. Studying the evolution of communication skills in monkeys will enable researchers to understand humans’ ability to understand much higher order syntax rules.
Compiled by Nandita Jayaraj
