Nature TTL

The mystery of dull coot parents but colorful chicks



- WATCH VIDEO: For some time scientists have been puzzled as to why coot chicks are colorful while their adult parents have dull colors. Here are some recent finds that might explain this anomaly.


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The mystery of dull parents but colorful chicks


The coot usually builds a nest from the stems of marsh plants. 

It makes it from living or dead plant materials, such as reeds and grass. 

The structure is almost always on the water as a floating platform.

Coot chicks are born with a colorful mix of black and yellow-orange feathers, unlike their dull black and white parents.

Scientists have long wondered why there is a big difference between the colors displayed by coot chicks and their coot adult parents. 

Colorful plumage in birds is mainly used for mating and courting displays. 

Often, male birds tend to be the ones attracting mates; hence they tend to be more colorful.

But this is not the case with coot chicks. 

They lose their beautiful colors by the time they reach sexual maturity. 

Furthermore, chicks are typically more vulnerable to predators than adults are, so why should they have bright colors? 

It has been a mystery for some time.

But now, scientists from the National Academy of Science think they've solved the mystery. 

In a study they published, the researchers explain how they found a correlation between coot chick color ornamentation and the order in which those chicks hatched. 

Therefore, it turns out that the chicks that hatch later become more colorful.

But why should this strange correlation exist? 

Researchers found that the coot parents have a strategy of picking favorites, making sure that the most colorful chicks are the best fed.

Initially, the first chicks get a head start in growth, but everything changes ten days after the last chick hatches. 

From this point, the parents start allocating more food to the younger ones to ensure they survive. 

Hence, the color code becomes very useful to coot parents to identify the younger chicks. 

Indeed, this is especially difficult to do when 8 to 10 chicks are scrambling for your attention.

A coot's nesting behavior also reveals that coots use a breeding tactic called brood parasitism. 

Brood parasitism is a breeding strategy where a female lays its eggs in a host nest to fool them into raising their chicks. 

However, according to a study by the University of California Santa Cruz, coots have learned to counter this by using the hatching order to recognize and reject the invader's chicks. 

So again, the color code comes in handy.

A coot needs to recognize its chicks to ensure they will be among those that will survive. 

It is critical as it is usually for a coot to have more chicks than it can raise. 

Therefore, some will inevitably die due to a lack of enough food. 

The chicks are reliant on their parent's feeding for at least a month, after which they start slowly becoming more independent.