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In 1949 the Costa Rican government abolished their army, stating that the army “would be replaced with an army of teachers.” The country has free universal public education and a literacy rate of 97%.

Costa Rica (/ˌkɒstə ˈriːkə/ (listen); Spanish: [ˈkosta ˈrika]; literally “Rich Coast”), officially the Republic of Costa Rica (Spanish: República de Costa Rica), is a country in Central America, bordered by Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, the Pacific Ocean to the southwest, and Ecuador to the south …

In 1949 the Costa Rican government abolished their army, stating that the army “would be replaced with an army of teachers.” The country has free universal public education and a literacy rate of 97%. Read More »

Della Porta (1563) invented a method of writing secret messages inside eggs. Ink transferred from the shell to the boiled egg inside. The message could only be revealed when cracked and peeled

“Della Porta” redirects here. For the architect, see Giacomo della Porta. Giambattista della Porta (Italian pronunciation: [dʒambatˈtista ˌdelːa ˈpɔrta]) (1535?[2] – 4 February 1615), also known as Giovanni Battista Della Porta, was an Italian scholar, polymath and playwright who lived in Naples at the time of the Scientific Revolution and Reformation. Giambattista della Porta spent …

Della Porta (1563) invented a method of writing secret messages inside eggs. Ink transferred from the shell to the boiled egg inside. The message could only be revealed when cracked and peeled Read More »

Male black-widow spiders tend to select their mates by determining if the female has eaten already to avoid being eaten themselves.

Latrodectus is a broadly distributed genus of spiders, which is composed of both black widow spiders and brown widow spiders.[3][4][5][6] A member of the Theridiidae family, this genus contains 31 species,[2] including the North American black widows (L. Female widow spiders are typically dark brown or a shiny black in colour when they are full …

Male black-widow spiders tend to select their mates by determining if the female has eaten already to avoid being eaten themselves. Read More »