Don Quixote and Saint John of the Cross’s Spiritual Chivalry

Despite its ludic appearance, “The adventure Don Quixote had with a dead body” (part I, chapter XIX) is one of the most complex pieces of Cervantes’ famous novel. In the midst of a dark night, the Manchegan knight errant confronts an otherwordly procession of robed men carrying torches who transport a dead “knight” on a bier. Don Quixote attacks them to “avenge” the mysterious dead man, discovering they were priests secretly taking the body from Baeza to Segovia. He wants to see face to face the relic of the dead body, but humbly turns his back, avoiding the “close encounter”. Curiously enough, his easy victory renders him sad. Cervantes is alluding to the secret transfer of St. John of the Cross’ body from Úbeda to Segovia, claimed by the devoted widow Doña Ana de Peñalosa. However, Cervantes is also establishing a surprising dialogue with St. John’s symbolic “dark night”, in which he fights as a brave mystical knight. Concurrently, he is quoting the books of chivalry‘s funeral processions and the curiosity of the occasional knight who wants to glance at the dead body. Furthermore, we see how extremely conversant the novelist is with the religious genre of spiritual chivalry, strongly opposed to the loose fantasy of the books of chivalry. Unable to look at St. John’s relic, an authentic knight of the heavenly militia, Don Quixote seems to silently acknowledge that there are higher chivalries than his own that he will never reach. No wonder he ends the adventure with a sad countenance, gaining a new identity as the “Caballero de la Triste Figura”.

Exposure to artificial light at night alters innate immune response in wild great tit nestlings

The large-scale impact of urbanization on wildlife is rather well documented, however the mechanisms underlying the effects of urban environments on animal physiology and behaviour are still poorly understood. Here, we focused on one major urban pollutant - artificial light at night (ALAN) - and its effects on the capacity to mount an innate immune response in wild great tit Parus major nestlings. Exposure to ALAN alters circadian rhythms of physiological processes, by disrupting the nocturnal production of the hormone melatonin. Nestlings were exposed to a light source emitting 3 lux for seven consecutive nights. Subsequently, nestlings were immune-challenged with a lipopolysaccharide injection, and we measured haptoglobin and nitric oxide levels pre- and post-injection. Both haptoglobin and nitric oxide are important markers for innate immune function. We found that ALAN exposure altered the innate immune response, with ALAN nestlings having lower haptoglobin and higher nitric oxide levels after the immune-challenge compared to dark-night nestlings. Unexpectedly, nitric oxide levels were overall, lower after the immune-challenge than before. These effects were likely mediated by melatonin, since ALAN-treated birds had on average 49% lower melatonin levels than the dark-night birds. ALAN exposure did not have any clear effects on nestling growth. This study provides a potential physiological mechanism underlying the documented differences in immune function between urban and rural birds observed in other studies. Moreover, it gives evidence that ALAN exposure affects nestling physiology, potentially causing long-term effects on physiology and behaviour, which ultimately can affect their fitness.