American Crow Dossier

by Carl Strang

Here is another, relatively long, entry in my series of species dossiers, accounts of what I have learned of various species from my own experience. In sharing these I am less interested in transmitting information than in encouraging you to think about what you know about these animals from what you have observed. When I started these records in the 1980’s I was embarrassed by how little I could say, and developing them was a good exercise in paying better attention when in the field.

Crow, American

Abundant around Culver, Indiana, in Cumberland County, PA, and [formerly] in DuPage County, IL. Strictly rural in the Culver area when I was a child, staying out of town [though this no longer is the case]. In PA, occurred in and out of town, but more typical of drier uplands and agricultural areas (the fish crow was more common in town and around rivers). In DuPage County, IL, American crows were abundant in both town and rural areas. They spend times in all habitats, though they stay up in trees when in the forest, usually. They spend more time in open, drier habitats than in others.

Their diet is equally diverse. I’ve seen them take corn sprouts, insects, young birds and rabbits, and carrion. In DuPage County they were the principal avian scavengers; vultures are practically nonexistent except during migration. Road kills are the most commonly observed food there. In late winter 1986 I saw a group of crows feeding on smooth sumac fruits, along the road at Warrenville, IL.

Crows nest solitarily, in the highest levels of forest trees. Vocalizations include a feeding call of young, a whining sound with somewhat the quality of a played sawblade: ree ree ree reereereereeree. This call accelerates and becomes slightly higher pitched and squeakier toward the end. Adults’ single “caws” appear to be contact calls. Harsher, sharper rapid clusters of caws are signals that rally crows to mob hawks or owls. This is a social, flocking species for most of the year, though spreading out when foraging for widely scattered foods like insects in short grass.

In DuPage County, crows mob great horned owls most frequently. Usually a mobbing begins with a single crow spotting the perched owl, and giving the rallying call. As more crows gather and add their voices, they perch all around the owl and the noise gets very loud. Usually the owl just sits stoically, but if it flies the crows give chase, sometimes one or two so bold as to peck the owl on the back. Eventually they lose interest, and silently fly off in one’s and two’s. Crows themselves are the objects of aerial harassment attacks by red-winged blackbirds.

Tall dead treetops with many branches in woods often are congregation sites.

10JA80. Boiling Springs, PA. In the afternoon I watched a crow chasing a kestrel. The birds flew high, and the crow stayed right with the little falcon’s twists, turns and dives. Finally, the crow broke off after the chase had carried the two a couple of hundred meters from the starting point. The crow flew back there, and the Kestrel flew a parallel course 50m away, but continued out of my field of view.

22FE87. Flock of 15 crows, flying. Cawing a lot, caws a little short though they aren’t chasing anything. Occasionally one utters a low, dry rattle. Later a loose group of four flew, taking turns making sets of 3-4 connected sharp caws. When calling, an individual folded his wings slightly and glided at a slight angle downwards.

14MR87. Signs of breeding. One, after cawing as though after an owl (none right there) broke off a twig from a treetop and flew away with it. Later a crow closely chased another out of that part of the woods. The chase went for at least 100m.

15MR87. Crow flying with beakful of soft material.

29AP87. Remains of a crow beneath great horned owl nest area.

16JA88. (McDowell?) Great horned owl flew to tree on west bank, just north of where trees thin to a thread of willows, where a housing development comes down. There’s a top-blown tree nearby, also several large oaks. Crows raising a ruckus, as though pestering a g.h. owl. From that direction a red-tailed hawk soared, but they paid it no heed. It circled an adjacent riparian strip, but when the owl finally broke and flew with a flock of 10 crows in pursuit, the hawk fell in between, and began to chase the owl, itself. Once it got above the owl and swooped at it, brushing the owl’s back with its feet, but about then the crows caught up and chased both raptors down toward where I had seen another owl perched, now out of my sight.

21MR88. Crows have been molting wing and tail feathers. Still chasing each other.

10AP88. 3-5 harsh, medium-fast caws apparently means “human here.” Several circled me at Hidden Lake F.P. woods, some perched in treetops above me and peered down, making that signal.

14AP88. Spotted 2 crow nests along Butterfield Rd., one beside construction site in a small grove of 30-40-foot-tall trees, the other well up in one of a grove of large oaks.

7MY88. Culver, IN. 2 nests high in oaks of “Indian Trails” area between town and Culver Military Academy. Adults flew off silently.

17MY88. I hadn’t seen the great horned owls of Willowbrook’s Back 40, or heard harassment by crows, since the restorational clearing of the marsh and fill area. Finally I saw 2, upstream of nest. Crows didn’t harass them for long or in numbers (2-3), apparently too occupied with their own nesting activity.

Harassment picked up, gradually, in June. On 18JE88 I observed heavy harassment of a great horned owl by a large number of crows at McDowell Grove F.P. Owl’s branching comes at the same time crows are starting to nest, and becoming too busy to harass owls.

18AP(MY?)88. The notes of a crow’s “human” call may be uttered rapidly when given as a warning. I walked into a riparian strip, one crow gave that fast version as I approached, and another immediately flew up from the streambed where it could not have seen me.

23MY88. Crow carrying medium-sized ear of dried corn, with about half of corn still attached, in beak.

29JA89. The crow mobbing call is a drawn out, often slurred, slightly burred caw, but retaining the abrupt start. (Another crow flying in, when still at a distance, gave a single note of this type but lazier, more drawled sounding, because it lacked the abrupt start and because it was more drawn out.)

7FE89. Permanently disabled crows in the exhibit cage at Willowbrook Wildlife Center responded to a “visiting” red-tail with short, uninflected (flat) caws with somewhat sharp beginnings but open ends. Fairly rapid, but not chattering-like, not clearly strung together. Many notes, long-continuing.

12MR89. A crow near Hartz Lake (Indiana) carrying a twig.

13MR89. DuPage County. Crow nest, same cluster of trees but farther back from busy Butterfield Road, as last year.

21AP89. A crow nest in downtown Chicago, in the little park across from the Newberry Library. I seldom have seen crows in the city. One bird visited the nest while I watched, but did not switch with the incubating crow.

25AP89. At end of a brief chase between 2 crows, one (I believe the pursued) gave a rattle-call. But I’ve recently heard the call from a bird perched for a long time.

10MR90. Crow with twig in beak, flying straight and parallel to road at 25mph.

30AP90. Crow chasing crow: a rattle call by the pursuing bird, with an emphatic inflection within.

12MR92, McDowell Forest Preserve. A Cooper’s hawk flew, northerly, high above woods. Pursued by a crow that occasionally swooped at it, but the hawk itself was nearly crow-sized, and it often turned and flew at the crow. Flight faster and more twisty then, but the crow turned to pursue the hawk when the latter resumed its path. Three such cycles observed.

20AU92. Cooper’s chased a couple crows at Herrick Lake F.P., not seriously. They rattle-called afterwards.

24JA93. Warrenville Grove Forest Preserve, IL. In late morning on a cold, sunny day, a goshawk flew past as I crossed a brushy opening in the forest. The bird was low, perhaps 10 feet up, and abruptly dipped, then flew up to a 15-20-foot-high perch on a large branch of a tree at the edge of the clearing. I came within 40 yards or so; the bird watched me but did not fly as I turned and skirted its position. Crows passing over gave several sets of quick, paired caws: “caw-caw, caw-caw, caw-caw,” merging in some cases into a fairly rapid series of cawing notes. This was not a response to me. Long after I left the site, I heard the same paired caws and looked back to see that the crows emitting them were circling above the goshawk’s position. The crows stayed at an altitude of ~1.5 tree-heights; the hawk was perched between 1/3 and ½ the trees’ height.

27JA97. Morning. Snow fairly deep. A red-tailed hawk flew over the College of DuPage parking lot with something in its talons, pursued by half a dozen crows. The hawk perched on a flat-topped, wooden light pole, began plucking prey while crows sporadically left nearby perches and swooped at it. After 10-15 minutes it flew away, and I checked the feathers, which were scattered in singles and small clumps over a 20×30 foot area: mourning dove. Crow calls resembled owl mobbing, but smaller number of birds and less sustained.

1997-98. I occasionally see a white crow as I drive to work at Willowbrook Forest Preserve, the bird on either side of Park Boulevard a short distance north of Butterfield Road.

15MR99. Crow flew across Butterfield Road near Naperville Road crossing, north to south, with sticks.

14AP99. Willowbrook. Crows seen chasing one another several times.

4MY99. At mid-day, a flock of 8 crows pursuing an adult great horned owl over much of Willowbrook Preserve.

25MY99. Blue jay mobbing a perched crow in top of dead willow, Willowbrook.

9DE99. Crows pursuing a red-tailed hawk in NE part of Willowbrook preserve.

2010. In recent years, crows have become scarce in DuPage County, apparently because of a lack of immunological resistance to West Nile Virus. The pattern seems to be that new birds disperse into the area in winter, and may attempt to nest (but this isn’t common as far as I can tell, supporting the idea that these are young, dispersing individuals). When conditions support the emergence of West-Nile-carrying mosquitoes in late summer, the crows vanish, apparently victims of the disease. Supporting this notion is the observation that in the cooler wetter summer of 2009, more crows persisted into the fall.

Literature Review: Turtle Evo-Devo

by Carl Strang

Evo-devo is a relatively new science that looks at embryological development, the genes that control it, and ties these measurements to the fossil record and other evolutionary data. This approach has brought amazing insights to all of these contributing disciplines, and enlightening elaborations to the overall story of life. Today I want to share some of what I learned from one evo-devo study published in 2009:

Nagashima, Hiroshi, et al. 2009. Evolution of the turtle body plan by the folding and creation of new muscle connections. Science 325:193-196.

Wood Turtle

This study focused on the unusual turtle body with its shell. A turtle’s carapace or upper shell is composed largely of the fused and expanded ribs and vertebrae. The lower shell is mainly the enlarged sternum or breastbone. The single oddest feature is the placement of the shoulder blades within the rib cage portion of the shell rather than outside as in other animals. The researchers traced the development process, finding that the ribs remain straight and short after an early period in which turtle development is like that of other amniotes (reptiles, birds and mammals).

Sea turtle

A disk-shaped region of back skin thickens to form a precursor to the carapace, and the ribs grow into this region and fuse to form the skeletal portion of the carapace. The body wall folds, limiting rib extension and moving the shoulder blades between and inside the first and second ribs. Muscle attachments for the legs shift accordingly, from other bones to elements of the shell. As is usual in development, this entire process is directed, step by step, by controlling genes that build upon and alter the sequence of events established earlier in the species’ evolutionary ancestry.

A Slow Start to Winter

by Carl Strang

Compared to last winter, this has been a slow one at Mayslake Forest Preserve in terms of animal activity. Last year, flocks of siskins and occasionally of white-winged crossbills frequented the preserve’s conifers. This year there have been only the year-round resident birds joined by a few American tree sparrows, and birds generally have been quiet.

Coyotes have been active, and we have seen them more frequently. I saw three together once, so at least one of last year’s pups has stuck around. Their tracks indicate the animals usually hunt individually, however.

In the deeper snow of January, the coyotes as always took advantage of human footprints and other depressions to make their own travel easier.

I did not see any mink tracks until January 12, where an individual was traveling along the little stream and went up onto the bridge.

Muskrats, as I believe I mentioned in an earlier post, have gone more to mound nests than to bank tunnels this year. There are two of these in the parking lot marsh.

A single such den in the stream corridor marsh projects only a little above the ice, and that animal may have been forced into a bank den.

I continue to enjoy my lunchtime walks on the preserve, and always am hopeful that I will find interesting animals or signs of their activity.

Winter Campfire 11

Winter Campfire 11

by Carl Strang

Winter is a time when we slow down and become introspective. Sitting and staring into the fire, we ponder the big questions. If you have been following this blog, you know that the focus here is science, science that can be done simply in outdoor settings. But we are more than scientists, and science has well defined limitations that need to be understood by everyone who does science or studies its findings. This winter I am using one post per week to develop my own viewpoint and biases, in particular sharing my take on the relationship between science and spirituality. In part this defines for me what these two realms of human experience are all about, and also develops the separate methods used for inquiry in each realm. I plan to place this paragraph in front of each entry in this series, so that those who are interested only in natural history or in scientific practice can skip these posts.

Chaos Theory

There are many valuable points of agreement between holographic ideas and chaos theory (John Briggs and F. David Peat. 1989. Turbulent mirror: an illustrated guide to chaos theory and the science of wholeness). Real world phenomena often are best described by mathematical systems in which simple factors, influences or patterns interact and repeat, folding back into themselves on each repetition (e.g., on each cycle of the wave). The resulting equilibrium state for the system takes the mathematical form of a strange attractor, a shape with fractional dimensionality. The fractional dimensionality results from the connectedness and constrained nature of the contributing factors, some needing to give way as others change. For instance, in the river metaphor, the water in the river is all connected and is constrained by the river’s banks. If some of the water forms a whirlpool, the water surrounding that spot must make space for it, and so is limited in what form it can take. Exaggerating that metaphor may make it clearer. If the river features are a little more solid, so that, for example, the entire river channel is filled with balls, then clearly moving one ball perturbs all the others as the energy of its movement is passed from one to the next. This example is limited to 3 spatial dimensions. If other, unseen dimensions are added, then folds in that extra-dimensional space could bring parts of that river (some of those balls) invisibly close to one another, so that perturbations could be spread strangely, appearing to jump instantaneously across 3D space. While our conventional senses could not perceive such connections, could this in fact be part of what intuition accomplishes? (You could call this the Mothers’ and Teachers’ extension of Bohm’s theory). In this framework, everything we do influences everything else, sometimes in unexpected ways, like a huge complicated dance.

Strange attractors thus reveal an interconnected wholeness to the universe. They also do so because tiny quantities are multiplied within them to become significant (the butterfly’s wing effect). For instance, the gravitational pull of the most distant star on a single atom potentially influences the system in which the atom plays a part. This feature of chaos theory demonstrates that everything can impact everything else. In addition, strange attractors are made up of smaller versions of themselves, a parts-reflecting-the-whole quality reminiscent of holograms.

Some Caterpillar Identifications

by Carl Strang

Recently I was looking back through some old photos, digital files from slides that I had scanned a few years back. Among them were images of two caterpillars which I never had identified. Referring to the excellent, relatively recently published Caterpillars of Eastern North America by David L. Wagner (Princeton Field Guides), I was able to confirm that one of these was the larva of the winter moth, or linden looper, which I featured in a recent post.

The other caterpillar, likewise in the inchworm family (Geometridae), was the larva of a moth called the half-wing, Phigalia titea.

As is typical of species that feed on woody plant leaves, this moth has a long list of hosts for its larval stage. Referring to my notes, I learned that I had found this nearly mature caterpillar on shagbark hickory at Meacham Grove Forest Preserve on June 5, 1984. In captivity it also had accepted cherry leaves (as in the photo). It had buried itself to pupate, and never had emerged. According to references, this caterpillar specializes on new leaves (i.e., ones that haven’t yet built up a concentration of defensive tannins), and so has only one generation per year.

Canada Goose M8R1

by Carl Strang

In a mid-December post I mentioned a Canada goose at the Blackwell roost wearing an orange neck collar with the designation M8R1.

I reported the sighting to the Canadian Wildlife Service, and recently got back a report in the mail. The bird, a female, was banded on July 24, 2002. She was an adult at the time, and so had hatched in 2001 or earlier. There was also a latitude-longitude location of where the goose was banded. I plugged the coordinates into GoogleEarth and got the following.

Close up, this proves to be a small lake close to the shore of Hudson Bay. Given the late July banding date, the goose probably was caught in a roundup of temporarily flightless birds that had gone to that lake while their primary and secondary feathers grew back. This is normal for waterfowl. Usually adult geese with young molt their primaries and secondaries so that those grow back just at the time when the goslings have completed their first set, so that all the family can fly together.

Winter Campfire 10

by Carl Strang

Winter is a time when we slow down and become introspective. Sitting and staring into the fire, we ponder the big questions. If you have been following this blog, you know that the focus here is science, science that can be done simply in outdoor settings. But we are more than scientists, and science has well defined limitations that need to be understood by everyone who does science or studies its findings. This winter I am using one post per week to develop my own viewpoint and biases, in particular sharing my take on the relationship between science and spirituality. In part this defines for me what these two realms of human experience are all about, and also develops the separate methods used for inquiry in each realm. I plan to place this paragraph in front of each entry in this series, so that those who are interested only in natural history or in scientific practice can skip these posts.

Bringing Quantum and Relativistic Physics Together

Certain theoretical and experimental outcomes of quantum theory demonstrate that events removed from one another in space somehow influence one another, as though communicating with one another, despite the fact that they are too far apart for anything traveling at light speed to connect them. These “nonlocal phenomena” or “entanglements” are difficult to explain. They exemplify a conflict between quantum theory and general relativity theory (i.e., both can’t be correct as currently understood) that scientists are attempting to resolve. The theorists’ emphasis on what happened at the Big Bang is tied into this conflict, because it is there that the universe was so small that quantum and relativity effects would have influenced one another strongly. During the Big Bang the universe inflated from less than marble sized to billions of light-years across in the first 10-35 second, a quandary again because of the implied faster-than-light speed. The universe now is understood to consist of a smattering of ordinary matter, much more unseen dark matter, ordinary energy, and a huge amount of poorly understood dark energy. This dark energy apparently is causing the universe to experience a newer round of less explosive but accelerating expansion. The first stars appeared 400 million years after the Big Bang, and we are now at the 13.7-billion-year-point seeing their grandchildren, stars of later generations.

Stephen Hawking devoted his 2001 book The Universe in a Nutshell to discussing theories of quantum gravity, which are needed to bring large scale general relativity together with small scale quantum uncertainties. Hawking is a proponent of M-theory, which is the current form of what earlier was called superstring theory (according to which the elementary particles all are composed of one-dimensional, string-like entities that vibrate in different ways to produce the different particles). M-theory, which also is strongly based on the physics of black holes, describes the universe as having been derived from the interactions of complexly vibrating, multidimensional “branes” (extra-dimensional expansions of the one-dimensional strings). These branes are said to be in close proximity, and their cymbal-like collisions create the wave patterns with holographic properties that we experience as our universe.

M-theory has the biggest following at present, but not all physicists buy into it. The leading contender is loop quantum gravity, described by one of its principal proponents, Lee Smolin, in a January 2004 Scientific American article. One basic idea of loop quantum gravity theory is that not only is matter composed of elementary particles, but time and space as well are built up of tiny indivisible units.

I recently finished reading another book on this subject, The Labyrinth of Time, by Michael Lockwood (2005). Lockwood delves more deeply into the history, derivation, advantages and limitations of the various theories I’ve been discussing, and adds other significant ones I haven’t mentioned. His book occasionally touches upon mathematical formalities that I don’t fully understand.  He characterizes the difficulty of bringing quantum physics and general relativity together by saying that no one has found a way to reconcile the changing curvature of space over time (i.e., space-time’s structure as general relativity describes it) with the structure of quantum fields that describe matter. I am left with the impression that while M-theory does indeed have the largest following among physicists, it requires flattening out the curvature of space-time, translating it into other terms that some physicists (including loop quantum gravity supporters) are unwilling to accept. These matters are far from settled. However, holographic properties of the universe are common to both M-theory and loop quantum gravity.

Today I will begin to discuss the universe-as-hologram notion more fully. That idea, along with the illusion of time as a separable quality, have the most profound impact on how to interpret our experience of this amazing reality, in my view. Here, I suspect that I am favoring what Lockwood refers to (p. 359) as “a strong holographic principle, which teeters on the edge of mysticism.”

One prominent physicist who has thought deeply about holographic properties of the universe is American David Bohm. My source here is Talbot’s Holographic Universe book. Bohm’s model describes the entire universe as a seamless whole (and so ties into Einstein’s notion that matter is folded space-time), but interconnected in such a way that each part reflects the whole. There are no “parts,” in fact, though the structure is differentiated. Bohm believes that all things are enfolded throughout the universe, which Bohm sees as an explicate order reflecting an underlying implicate order that ties it all together. His own term for the model is “holomovement,” so as to avoid the static image of a hologram.

I was fascinated to read that one of Bohm’s metaphors is one I came up with on my own in 1986. I was walking in Maple Grove Forest Preserve in late March, practicing advanced awareness techniques. Quoting from my journal: “At one point, as I succeeded in becoming … sensitive to the forest around me, I grew conscious of the fact that I am not as separate an entity as my ego would have me believe. Rather, I felt that I was a focus or eddy of energy within the matrix of the spiritual flow of reality.” I was struck by the notion that we all could be part of a universal whole, and yet entities of our own, if we were like river or lake features. In a river there are tiny whirlpools, waves, eddies, holes and so forth that are part of the river and its flow and yet are distinguishable features. Their boundaries are more or less distinct, though the closer you look the harder they are to draw. Lakes similarly have waves which cycle through increasing energy until they crest, then start over again.

Compare that to this description of a Bohm metaphor as passed along by Talbot (p. 49): “…he points to the little eddies and whirlpools that often form in a river. At a glance such eddies appear to be separate things and possess many individual characteristics such as size, rate, and direction of rotation, et cetera. But careful scrutiny reveals that it is impossible to determine where any given whirlpool ends and the rest of the river begins” (though the location of that boundary sometimes is very important to whitewater kayakers). “Thus Bohm is not suggesting that the differences between ‘things’ is meaningless. He merely wants us to be aware constantly that dividing various aspects of the holomovement into ‘things’ is always an abstraction, a way of making those aspects stand out in our perception by our way of thinking.”

Sheik Khaled Bentounès (2002. Sufism: the heart of Islam) describes an Islamic perspective that sounds like this characterization of the holographic universe: “In our tradition, we say that the entire universe is contained in the four Holy Books, the four Holy Books in The Qur’an, which is itself contained in fatiha, itself contained in the invocation, the basmala (in the name of God, Most Gracious, Most Merciful), which is contained in the letter ba (ب ), itself found in the dot under letter ba. We go from the universal, from the infinitely great to the infinitely small, from the macrocosm to the microcosm―the dot―which is the origin of all things. It is the dot that contains the whole universe.”

Here’s another relevant quote from Bentounès: “I discover that to love others is to love God, and is also to love oneself, for many people hate themselves; they do not accept what they are. By doing so, they do not accept God, when that which He has made of me and what He has given me is true and right. As a creature, I must be aware of this fact and love what I am. We are not talking here about the love of the ego. Our individuality does exist, but in fact it integrates into the Ultimate Being and harmonizes itself with the whole, just like the grain of sand in the dune; unfortunately people usually live to care for this individualistic ego which seeks but its own interest and which breathes for no other reason but to satisfy its ephemeral needs.” He also makes reference to the wave metaphor, quoting a poem by Sheikh Al Alawea: “They realized that every manifestation / Is identical to its root / For the wave is no longer seen / In the immensity of the ocean.”

The holograph idea adds depth to the Golden Rule, and to the notion that healing acts of any kind heal the whole, not just the person or place to which the healing is applied. I will have more to say about the implications of holographic ideas, as well as those of time-as-illusion.

Literature Review: Monarch Navigation

by Carl Strang

If I had to choose one scientific journal to follow, it would be Science. Not only is this the most prestigious American journal (on par with Europe’s Nature), it is available at many public libraries and all college libraries. In addition to the original scientific papers published in Science, there is excellent reporting on results published elsewhere. Today I want to focus on one of the papers published in Science last year:

Merlin, Christine, Robert J. Gegear, and Steven M. Reppert. 2009. Antennal circadian clocks coordinate sun compass orientation in migratory monarch butterflies. Science 325: 1700-1704.

One of the wonders of nature in North America is the monarch migration. Each autumn, monarch butterflies from across eastern North America fly to a small area in the Mexican mountains and spend the winter there. They are removed by several generations from their ancestors who last made the trip. How do they navigate?

These three researchers looked at an aspect of this question. They knew from earlier studies that monarchs orient toward the sun to move in a southerly direction during their fall migration. Furthermore, the butterflies use a physiological clock (consisting of certain chemical reactions) to tell them where the sun is relative to south. This study found that the clock is located in the antennae rather than in the brain as had been thought. I would have guessed that persistent pheromones were involved somehow in monarch navigation, the butterflies perhaps following gradients of concentration with the aid of sensitive chemoreceptors in the antennae. It seems from this study that the antennae are indeed involved, but in a completely different way.

House Cleaning Spider Inventory

by Carl Strang

Earlier I described my impressions of how three species of house spiders distribute themselves in my home. During a recent round of house cleaning I took a mid-winter inventory of them. I was surprised to find them more widely scattered than I expected. I had thought they would be confined to the more humid bathrooms, but such was not the case. I found none in the upstairs bathroom, but 5 in other upstairs rooms (all Pholcus, the daddy-long-legs spiders). As expected, many more were downstairs, with the greatest concentration (10 Pholcus and 1 Achaearanea) in the downstairs bathroom. Other downstairs rooms held 17 Pholcus and 1 Achaearanea. I didn’t run across any Tegenaria.

During the house cleaning I removed all unoccupied cobwebs, and cleared away the husks of discarded prey. The latter process inevitably disturbed the webs of spiders that had set up near the floor. Their response was clearest in the downstairs bathroom, where a few Pholcus and the 1 Achaearanea were at floor level. After the cleaning, the Pholcus all moved up to the ceiling.

The single Achaearanea stayed near the floor, but moved into a more protected corner created by the door frame.

Only that last spider now is in position to take advantage of the most common winter prey, tiny ants.

I realize that this description probably makes my house seem like a scary place. These all are tiny animals, however, and most are hidden in out-of-the-way corners. As I said, I was surprised to find them in rooms other than bathrooms, when obviously they had been in those places for some time without attracting my attention.

Winter Campfire 9

by Carl Strang

Winter is a time when we slow down and become introspective. Sitting and staring into the fire, we ponder the big questions. If you have been following this blog, you know that the focus here is science, science that can be done simply in outdoor settings. But we are more than scientists, and science has well defined limitations that need to be understood by everyone who does science or studies its findings. This winter I am using one post per week to develop my own viewpoint and biases, in particular sharing my take on the relationship between science and spirituality. In part this defines for me what these two realms of human experience are all about, and also develops the separate methods used for inquiry in each realm. I plan to place this paragraph in front of each entry in this series, so that those who are interested only in natural history or in scientific practice can skip these posts.

Relativity

The physics I’ve been describing so far is quantum physics. Relativity is another branch of physics with its own surprises. Relativity theory and its large body of experimental support demonstrate that our every day perception of three dimensional space is misleading. Time is a fourth dimension that needs to be considered in combination with the three dimensions of space, and the resulting four dimensions interact in such a way that there is no space apart from time, there is no time apart from space, there is only space-time. This is a meaning of the constancy of c, the speed of light. No matter how fast one is moving relative to the light one is measuring, the speed of that light always proves to have the same value.  As one’s velocity changes, space and time also change so that c is measured the same because one’s measuring devices change. Clocks speed up or slow down, rulers shrink or expand relative to those elsewhere.

Furthermore, space-time is curved. It would be simpler if the three dimensions of space and the one of time were all set up with every dimension always at right angles to all the others. But they are not. They are curved. If we could see the orbit of a planet in the four dimensions of space-time, it would be seen as following the easiest, shortest path. All we can do is see the projection of that path onto the three dimensions of space, so it has, to us, an elliptical spatial orbit around the sun. Past, present and future all would be visible at a glance if one could view them in the four dimensions of space-time (sometimes referred to as block-space-time). Yet we are confined to three spatial dimensions in our experience, so time and space for each of us meet at a unique point, the here and now, the center of the Universe.

Be here now. Henslow’s sparrow is a good teacher of living in the moment. Bird book authors scorn its simple little song, but to me the bird seems to be saying the same word, over and over: “decision, decision, decision…” It’s a reminder that our consciousness is focused in the present moment in time, and we are free to act in that moment. Each moment demands its decision. (This seems to be a contradiction to block-space-time’s declaration that the future already is set; my contention is that consciousness, apparently moving along the axis of time, allows us to make the decisions that create the shape of that future. I’ll elaborate on this point later in the series).

Einstein’s most famous equation not only points to the constancy of the speed of light, it also says that energy and mass are the same thing. What is it that bends space-time into curves? It is the presence of matter, of mass. Physicist John Wheeler: “Mass tells space-time how to curve, and curved space-time tells mass how to move.” But mass is energy, and mass is all those insubstantial, probabilistic little quanta. According to Zukav (p. 179), Einstein intuited but never developed mathematically the idea that “a piece of matter is a curvature of the space-time continuum!” Matter itself thus may be composed of folded space-time. (And then there’s Einstein’s “extra-special” theory of relativity, about the tendency of the matter from hot fudge sundaes to unfold and expand inconveniently).

Here’s another strange one: the Universe is all expanding out of one point. At the instant of the Big Bang we all were in the same place, and all places were there within that single point. Thus from the perspective of every place and every thing, the rest of the Universe is expanding away from it equally in all directions (What? I have bad breath? What?). This lends a scientific foundation to the mythic idea that each of us, every place, is in fact the center of the Universe.

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