Are Asteraceae 1.5 Billion Years Old? A Reply to Heads

Hard Heads and Open Minds: A Reply to Panksepp (2003)

In the authors’ original article (M. S. Blumberg & G. Sokoloff, 2001), they provided evidence that the ultrasonic vocalizations of infant rats are acoustic by-products of a physiological maneuver. In J. Panksepp’s (2003) comment, he sidestepped the authors’ empirical findings and focused on his concern that their perspective might prevent progress toward his ultimate goal of understanding the n...

Structure and function of a compound eye, more than half a billion years old

Until now, the fossil record has not been capable of revealing any details of the mechanisms of complex vision at the beginning of metazoan evolution. Here, we describe functional units, at a cellular level, of a compound eye from the base of the Cambrian, more than half a billion years old. Remains of early Cambrian arthropods showed the external lattices of enormous compound eyes, but not the...

Mitochondria—A billion years of cohabitation

An engulfment of a small bacterium by a larger archaeon more than a billion years ago resulted not in death, but in one of the most successful partnerships on earth. As you sit there, each of your cells (apart from your red blood cells) contains hundreds or thousands of the descendants of that bacterium, still earning their keep as part of that endosymbiotic deal struck in some ancient pool. Ho...

The First Four Billion Years

Designing a model of curriculum for teaching philosophy to preschool children (3 to 5 years old)

The present study was conducted to design a philosophy curriculum model for preschool children aged 3 to 5 years based on nine elements of Klein. To achieve this goal, has been used synthesis method in pattern design. The scope of research was documents in the field of philosophy for children which by purposive sampling 50 articles (25 Persian articles and 25 Latin articles) was selected. The p...