Cowbirds Display Counting Skills

They must determine ideal times for getting other birds to incubate their eggs.

SUMMARY: Several species of animals are known to have simple counting abilities including some primates, birds, and dogs. However, there has been little research on how these animals use these abilities in the wild.

David J. White of the U. of Pennsylvania and some colleagues now have discovered how one bird species, the brown-headed cowbird (picture from Wikimedia Commons), uses some fairly exacting arithmetic skills when it comes to incubating its eggs.

The cowbirds trick other birds into doing the incubating. Usually, the host birds they target are ones which will lay an egg every day for several days, then stop after three to six eggs are in the nest. The cowbirds look for a chance to sneak one of their own eggs into the host birds' nests, but usually wait until at least three eggs have been laid.

For this trick to work, the cowbirds need to know that incubation hasn't begun. As it flies by a target nest periodically, a cowbird has to be able to count the eggs so that it knows the host bird is still laying an egg a day and hasn't yet started incubation. If it waits too long, it will be too late to deposit its own egg or, as it sometimes does, remove one of the host bird's eggs.

White's team did tests using artificial nests in which they added fake eggs at different rates. They discovered that the cowbirds would avoid nests if the number of eggs was less than the number of days that had elapsed. "The ability of females to remember egg number and compare changes in egg number across days allows them to select nests most suitable for parasitism," the researchers concluded.

To read the entire article click on this link to WORLD SCIENCE.

COMMENT: It is becoming quite obvious that to call someone a "bird brain" should no longer be considered an insult. Like all of God's creatures, birds have been given some amazing abilities including this gift of simple arithmetic. (For a previous post that examined in more detail the intelligence of some bird species, click on this link to our May 11 post, Bird Brains Amaze Researchers.)

The reader can decide what is more reasonable, to believe the cowbirds developed this talent as the result of natural processes or to believe they were given this ability by their Creator. Hardly a day goes by that we don't learn something new and remarkable about the world and its living inhabitants. Praise the Lord for his earthly treasures and also for the heavenly treasures He offers free to all who accept them through faith in Jesus Christ as our Savior from sin.

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QUESTION OF THE DAY

Is it possible to be sued for what one writes on the Internet?

Yes. A blogger was ordered to pay $1.8 million for defaming a lawyer. Also, a tenant was sued for $50,000 for criticizing her apartment online. And someone wrote a negative review online about a chiropractor who filed a suit and settled out of court. Generally, free speech is protected on the Internet, but defamation of character could cause a problem.

Source: Parade (September 20, 2009)