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Thursday, September 10, 2020

Loved and trusted or objectified?

 


The short blast of hummingbird migration, mostly in form of super aggressive Rufous Hummers, has passed the desert. A lone Costa's male is again king of the realm. We named him, or his predecessor Charlie years ago. The hummingbird feeder is emptied every night by Lesser Long-nosed Bats, But thanks to Randy's diligence Charlie hardly notices that intrusion. 

We are sitting at our patio table having breakfast. Since the sun is reaching into the depth of the patio, Charlie pays little attention to his sugar water feeder. Instead he regularly takes off from his roost on the chain of an empty planthanger to buzz my face, my bare shoulders, arms and hands. What? He pays much less attention to Randy, who is covered by his usual long-sleeved, pearl buttoned western shirt

Today, the intrusive bird is not the only annoyance. Little flies, less than 2mm long and with a fat, light colored abdomen keep landing on my skin or hovering in front of my eyes. If those are no-see-ums the name does not quite fit: I can see them dancing in the the rays of the rising sun. Nearly like dust particles, but not quite. 

When Charlie finally picks one from my arm I am sure that the bird's behavior is correlated to the prevalence of those bugs on this cool, sunny morning. He can obviously see them very well. He even grabs them out of the air in front of my nose. He is molting, so I guess he can use the proteine.

I know that many bird watchers would be happy to have a 'trusting friend' like Charlie defending them from intrusive bugs. But being a sceptic, even a cynic, and a scientist, I have a different interpretation. The bird is certainly used to us - we sit there quietly eating, reading, solving cryptoquips and sudokus, every morning, all year round. We are part of the landscape. Depending on barometric pressure, temperature, wind or humidity, skipped shower after running, we attract different numbers of those little insects. Like any warm rock, tree trunk or flower. By not showing any fear, Charlie is not showing friendship or trust, but simply objectifying me. I am sure he never thinks of me by any name ...



Tuesday, September 8, 2020

September Morning


 A cool and hazy morning - finally a sign of autumn? The sun hung there like a red balloon, burning neither my retinas nor the skin of my shoulders. There was no wind and no bird song. For days, there have been quail or dove hunters around, which probably explains why the birds seemed subdued. In the old ironwood skeleton that marks the turn-around of my morning run hunkered a dark shape. A vulture? As we came closer it unfolded itself into hawk-silhouette and screeched: Old Dark Female (RT) who has now greeted me like that for more than a decade - screaming like a fake eagle in a klishee western movie whenever I enter her territory, now even in early September. Without the lift of raising warm air, she took off on heavy wings and turned around rather soon to roost again - and screech some more

Friday, July 31, 2020

The end of July 2020

Running northwest for a mile and a half among creosote and saguaros. The setting sun just barely off to the left, so not in my eyes. The sand under my feet is dry and springy, then, when I follow a wash, deep and soft. The dogs are chasing lizards. 7:10 pm and still 109 degrees. Turning back, going southeast now. Thunderheads loom over Wassen Peak. To the right, still building and growing, sharply modeled in bright whites and yellows by the sun that has dipped under the horizon from my  point of view. To the left, anvil shaped and floating apart, rain streaking down on the Tucson Mountains or virgos withering away without reaching the ground? Pink and ominous purple. Lightning striking across and seeking the peaks. Above the cold white moon in the still icy blue sky. Night hawks streaking by me, very fast, though their wing beats are slow. I believe that I can hear them slicing the air. Which is getting heavier. I am not running now. The dogs let their slobbering tongues hang. Will those fit back into their mouths? Will they have to curl them around loosely floating brains, woodpecker-like? No. Those tongues will eventually, but not very soon, deflate and shrink again. Back home at 7:30. Still 106 on the patio 

Wednesday, July 15, 2020

Night Hawks as Weather Forecasters


 We live between Saguaro National Park West and the Santa Cruz River. Every evening just before sunset, I run about 2 miles with one of my dogs. Chaco and Kira take their turns in that.  On my way home, running south, I always encounter several dozens of Lesser Night Hawks that are moving from their breeding grounds in the Tucson Mountains (including our own backyard) to their nightly feeding area at the river in Marana. They appear like clock work as soon as the sun touches the horizon, and they always all fly in the same direction - north. In May and June, they were usually silhouetted against the sky because they were flying quite high. 

Lately, they come in low, dodging saguaros and even me and my dog on their way, and impossible to photograph. 
My grandmother in Germany always told me to watch if swallows and swifts were flying high: more sunshine to come. Low flying swallows: rainy days ahead. Now I think it's the bugs that fly high or low and insectivore, on-the-wing-hunting birds are just following suit. The bugs may be influenced by the barometric pressure changes, or the coming rain just brings out different bugs. My grandma was certainly as good as any weather forecaster in the seventies in Germany


Sunday, June 7, 2020

Night of the Queen 2020


The COVid19 numbers are sky-rocketing, the timeline indicating that the Memorial Day and Mothers Day weekends with dropped lock-down have more to do with it than the protest marches, but they will also soon show consequences. AZ hospitals at capacity, Better not get sick here now.  I am dreading my gallery duty on the 11th of June.

Photo by Shawna Caldwell: How the fire in the catalinas started
Not to forget that other, probably greater problems loom: Global Warming is pushed out of the news, The slowed-down world economy may provide a small reprieve.   But our weather patterns are ominously confusing.  We had monsoon like thunderstorms for several afternoons, nearly a month too early.


Push Ridge fire by Bill George
Result: fires. We can see them glowing at night and the smoke now. The second photo was taken by a friend who lives in a development that was carved into the mountains about 15 to 20 years ago, so I remember open desert there. 


But some eternal (?) natural rhythms are still operating: last night was the night of the Queen.  Once a year a twig-thin cactus (Peniocereus greggii) produces the most beautiful, fragrant flowers. The Mystery: within miles, they all open at once. I have not been able to relate it to moon phase, temperature, day length (the date can vary by a month) or precipitation (usually there is none before the cacti bloom) barometric pressure - nothing I can measure seems to provide the trigger, and yet, they are completely synchronized. Usually, Tohono Chul Park close to Tucson monitors and celebrates the bloom, so people are aware of the event. This year the park is closed. This morning, I found several on our dog walk. We live right in the middle of a big population. This year there were fewer flowers than usual. 




Honey Bees were all over the flowers in the morning sun. These opportunistic generalists among bees are probably not suited to pollinate the big flowers. That is probably usually done by big Manduca and other Sphinx Moths. But those have been out in numbers a couple of weeks ago. I saw them at my black lights.   At the moment they seem rather scarce.  Perhaps I just do not see them at my lights because the moon is rather full..

Peniocereus greggii, Queen of the Night

By the 12th of June the Big Horn Fire in the Catalinas had spread. The inferno came down the mountain towards foothills homes and 100s of people had to evacuate, others are on stand-by.

View towards the Catalinas from Tucson on June 11th 2020








Natures Gifts - Raptor Feathers

Female left, male right Harris' Hawks
5 Harris' Hawks are hanging around for days now, watching us from breakfast to last evening walk. Maybe they like the new big birdbath that I put out across the street? There they left a beautiful feather. For me? Or does it come from the pair of Cooper's that also frequents that yard? Legally I'm not even allowed to pick it up. At the base, it has a light part with some freckles and the darker part of the vane is subtly banded. It looks very much like the eagle feathers on Native American festive gear, just much smaller. At its tip it shows traces of at least a year of use.. Only the strong rachis and some hard barbs are left to form a sharp, bleached out point
Harris Hawk tail feather, probably from a juvenile

Thursday, May 21, 2020

My own, very personal response to the virus threat:


My own, very personal response to the virus threat:

ACE2 is an integral membrane protein that appears to be the host-cell receptor for SARS-CoV-2

In the beginning of this pandemic, My friend Tom McDonald (physiology professor U of A) mentioned some research data from China that referred to increased vulnerability of lung tissue after treatment with Losartan-class blockers. The rational was that hypertension treatment with angiotensin-converting enzyme 2 (ACE2) receptor blockers, to which SARS-CoV-2 binds, might in the long-run increase the number of those receptors (often the case with receptor blockers). As the virus binds to those (increased in numbers) loci, lung tissue may be more vulnerable
. Recently, another theory, was that Losartan may block enough receptors to actually protect the tissue from the virus - may prevent organ failure on a wide range in C19 patients and thus.was considered among possible treatment options.
But most patients who died were hypertensive and receiving treatment.
So the thinking now goes back to the earlier idea : "Two recent studies, however, have poked holes in this hypothesis (that losartan could be used to treat C19 patients). In the first study, researchers raised the possibility that antihypertensives, including losartan, could actually induce the body to make more ACE2, increasing the ability of SARS-CoV-2 to bind to and infiltrate cells. In the second study, Italian researchers found that three-quarters of patients with COVID-19 who died had hypertension. Antihypertensive treatment may have been the reason for their increased susceptibility."
Anyway, Tom's very first mentioning of the possible connection made me look more closely into my own treatment with Losartan. It is the only drug I was taking and I did never like doing so. So in early March, I started a running regiment - twice a day 1 to 2 miles - I have lots of time on my hands after all art shows were cancelled! I monitored my BP and weight and after both began decreasing I started going off Losartan in small steps. Surprisingly, my BP was not at all correlated to the drug dose, but very much to body weight. I went from 170 pounds to 155 without fasting, and my BP is in a healthy normal range now.
The conflicting theories about Losartan show how very difficult and intertwined physiological processes and the reaction to drugs really are, and why it is often so difficult for the scientific community to make easily understood yes-or-no statements. Sadly, this opens up the discussion for loud-mouthed science deniers. As a physiologist myself, I am in a position to at least make somewhat educated decisions for my own health. Whatever the outcome of the Losartan studies concerning the virus will eventually be (I expect a difference between long-term chronic use and short, high dose treatment) I feel much healthier and fitter than in a decade. So thanks to my friend's push