From sunrise to sunrise, with veiled face lifted and arms and wings outstretched, this blessed celestial being keeps watch over us all, sinners and saints alike. Imbue with intent in your tradition to invoke the protection aspect of this icon. From Cesare Ripa, Iconologia 1669

The Dance of Death - From Modern illustration, by Joseph Pennell, London 1895

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Consider these esteemed gentlemen as they ponder the nature of mortality.

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Consider these esteemed gentlemen as they ponder the nature of mortality.

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Tabula I Libra I is a classic image from the Fabrica. Is he expounding on the nature of mortality?

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Tabula I Libra I is a classic image from the Fabrica. Is he expounding on the nature of mortality?

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Tabula II Libra I is a classic image from the Fabrica. Is he pondering his own mortality?

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Tabula II Libra I is a classic image from the Fabrica. Is he pondering on his own mortality?

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Tabula III Libra I is a classic image from the Fabrica. I call him the Weeping Skeleton. Is he bereft from contemplating his own mortality?

Published in 1543, Andreas Vesalius's 'De Humani Corporis Fabrica' was a groundbreaking book on anatomy. Tabula III Libra I is a classic image from the Fabrica. I call him the Weeping Skeleton. Is he bereft from contemplating his own mortality?

1733, Osteographia or The Anatomy of Bones. William Cheselden was a surgeon and anatomist, whose illustrations were the first full and accurate description of the anatomy of the human skeletal system.

1733, Osteographia or The Anatomy of Bones. William Cheselden was a surgeon and anatomist, whose illustrations were the first full and accurate description of the anatomy of the human skeletal system.

A creature of myth and legend, the Irish Deer was the largest of its species.

A creature of myth and legend, the Irish Deer was the largest of its species.

From the Royal Natural History archive, the skull of the Babirusa.

From the Royal Natural History archive, the skull of the Babirusa.

1854, London, Natural History illustration by Charles Knight

1854, London, Natural History illustration by Charles Knight

By Georges Cuvier, French naturalist and zoologist, sometimes referred to as the "father of paleontology".

By Georges Cuvier, French naturalist and zoologist, sometimes referred to as the "father of paleontology".