Category Archives: Evolution

Hummingbirds in the Real World: evolution, physiology and relationship

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Giant Hummingbird, Patagona gigas on Cactus in Peru, by Devon Pike

Hummingbirds are clearly fascinating and engaging creatures.  They are biological wonders of ‘invention’, little gems that sparkle in their airborne dances through sunlight, with the seductive power to capture the attention of even the most incognizant of us lumbering earthbound humans, including many of those pretty much blind to the natural world.  I did not set out to write this piece, I was researching several Puya species of the South American Andes, curious about their survival and pollination and became intrigued by these miraculous little fliers.  Part of our fascination with them I think is attributable to their size.  There are 338 known species today, 104 genera, which as a group comprise the entire Hummingbird family, the Trochilidae, the second largest bird family found in the Americas, numbers that speak to their success that many ornithologists say ‘could’ continue to increase over the next several million years!  The species range in size from the tiny Bee Hummingbird, of Cuba, about 2″ long and less than 2 grams in weight to the 9″ long, 24 grams, that’s around 3/4 of an ounce, of the behemoth, Giant Hummingbird found in much of the more arid western Andes from Ecuador south into central Chile.  The Giant, Patagona gigas, is the sole species of its genus, though there is a subgenus that is found into Ecuador,  and it is thought to be about as large as any Hummingbird can be.  Any bigger and it is thought that those characteristics that differentiate Hummers from other birds become more difficult to sustain. Continue reading

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Puya: Growing These Well Armed South Americans in the Pacific Northwest

[I wrote this originally about 2 years ago as part of what turned out to be a too long look into the Bromeliad Family.  Here I present only the genus Puya spp. in an edited form with the addition of the species Puya berteroniana.  Go to the original article to read about the shared evolution of the several genera and families that comprise the family, why these are not considered succulents and a look at the armed defenses of many plants.  My plan is to breakout at least some of the other genera as well as I think the length of the original post may have put some readers off.]

Puya: one of the Xeric Genera of Terrestrial Bromeliaceae

The name “Puya” comes from the Mapuche Indian word meaning “point” (The Mapuche people are indigenous to Chile and Argentina.  They constitute approximately 10% (more than 1.000.000 people) of the Chilean population. Half of them live in the south of Chile from the river Bío Bío to Chiloé Island. The other half is found in and around the capital, Santiago and were mostly forced to the city after Pinochet privatized their lands giving them to the wealthy.)…the assignation is clear and the pointed, spiky, nature of this genus is immediately obvious to anyone.  But there is something easy and comfortable about the sound of the word in your mouth when you speak it…poo-‘yah.  Puya are native to the arid portions of the Andes and South American western coastal mountains.  (Oddly, two species are found in dry areas of Costa Rica.)

Puya spp., populate arid western regions of the Andes Mountains up into southern Central America.  These are terrestrial plants, relying on their roots to find the moisture that they need.  They possess the same basic rosette structure common to all members of the Bromeliad family to which they belong, including their petiole-less leaves, which clasp directly to a compact stem structure, funnelling the infrequent, and seasonal, precipitation they get into their crowns and root structures where they can take it up, a strategy very similar to Agave and Aloe which grow under similar conditions. Continue reading

Ginkgo biloba: on reproduction, evolution and anomalous existence

There are six Ginkgo trees here along Main St., on the north side Chapman Square, downtown, they are the most abundant species on the two blocks and the smelly not-a-fruits that drop in the fall demonstrate that many of them are female.. You can see the Elk fountain, one of several fountains once installed so locals could ‘water’ their horses. Only two the Ginkgos on the two blocks are male clones that I know of, the others are a mix of male and female seedlings. The male strobili are still in evidence on the trees. The female trees appear to hold their strobili on higher branches, as I could see nothing on the available lower branches with my bad eyes.

Mid-April and the Ginkgos are flowering….well, technically not ‘flowering’, because they aren’t angiosperms.  Botanically speaking, they are doing what they do instead, forming the little structures that contain their sex organs for what would most likely be failed attempts at reproduction.  Think about it, in a community filled with males no progeny will be produced.  We were on one of our walks down an inner section of Tri-Met’s Orange Line, approaching the Tilikum Bridge, when I noticed this event…I was a little surprised.

If you know much about Ginkgos you probably know about their fruit, which again is not technically a ‘fruit’ because they aren’t angiosperms and only angiosperms form ‘fruit’, but their ‘fruit like’ structures are notoriously stinky when they become ripe, smelling like what many describe as being similar to dog ‘poo’, others liken it more to ‘vomit’, either equally unpleasant, when they fall to the ground and splatter or are stepped on…one of the reasons why these trees are cloned, grafted, by the nursery industry….By cloning selected forms propagators allow us to remove the chance of purchasing a female tree…unless in their zeal to bring a particular form to market they select a tree that hasn’t flowered yet….Without looking at their chromosomes, it is nearly impossible to determine the sex of a juvenile tree.  Clones stay true to their sex, so if their scion wood, or buds, are taken from a male tree, the result will be a male clone.  Ginkgos are a dioecious species, ‘di’ meaning two, so any one individual plant produces only male or female structures, so it takes two trees, of opposite sex, to produce viable seed.  Monoecious means that an individual plant produces male and female structures.  In Ginkgo spp. and the non-flowering gymnosperms these sexual structures are called stobili or singularly, a strobilus. Continue reading

On Our Expulsion From the Garden: How Our Ideas of the Garden Shape What We Do

There are those who argue that life is short and violent, that we have nothing to look forward to other than our deaths…so we might as well grab for whatever we can now!….that is the path of the nihilist and the greedy, it serves as an excuse, a rationale for their choices, following an ethic of ‘why the hell not!’  This is consistent with the ‘beliefs’ of those who feel the weak get what they deserve, that anything that opposes their idea of dominance, is weakness and failure and they pursue it with the righteousness of a ‘true believer’.  “Only the strong survive”.  If our gardens can teach us anything it is instead that, ‘He/She who has the graciousness to take only what they need and gives back whatever they are able to, live on through the love and lives of those and that which they’ve nurtured, helped, befriended and mentored along the way and in this way have helped build a richer, more complex and diverse world.’  Our true legacy will be best expressed in the richness and health of the world we leave behind, of those that we’ve loved and taught.  As competitive as the world is, it is this positive, cooperative, supportive aspect of life that makes it all possible.  While the world is divided into heterotrophs and autotrophs, those that must consume to live and those able to grow and metabolize that which they need from the world around them, it requires them both, working in a balance to sustain them all.  We humans, ultimately, cannot be any different if the world is to continue on. Continue reading

Winter 0f ’18 -’19: Cloudy, Mild With a Chance of….On Weather, Zones & Plants

It’s 41ºF at 5:30am on Mar. 12 as I begin to write this.  We appear to have come out of the longest sustained ‘cold’ period of the winter of ’18-’19 which began on February 4 and continued through Mar. 11, a period of 36 days.  Over those days we had freezing minimum temps at PDX, the official NOAA reporting station for the Portland area, on 26 of them.  On two of those days, Feb. 6 and 7, PDX recorded the winter’s lowest temp, 23ºF, making it a zn 9a winter, mild for us historically and especially so for the temperate US as a whole, much of which was experiencing its own much colder temps.  It’s mid-March and our high temps have climbed well above what they were and our forecasts call for milder, more ‘normal’ highs and lows now locally.  It looks likely that not only are we going to be on the ‘warm side’ of normal, but that our lows have shifted into a pattern well out of the freezing range.  (State ODF meteorologist, Pete Parsons, calls for a pattern of slightly warmer and drier weather than normal over March, April and May with the highest chance of this during May.) 

While weather consists of moments, recorded data points, we attempt to make sense of it in its patterns over time…our experience of it.  In this we are much like our plants.  Plants too have their ‘expectations’ of the weather and those conditions that take them outside of them, outside their familiar patterns, the relatively quick changes and perturbations, as well as the longer sustained patterns, and extremes, are ‘noticed’ and make a difference.  How does this winter compare? Continue reading

Fabiana imbricata: the Andean Un-Tomato, a Non-Heath That Looks a lot Like its Cousin Cestrum

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Fabiana imbricata has an appearance much like the upright and shrubby Erica arborea…maybe mixed with an upright form of Rosemary…providing a remarkable texture in the garden.

In gardening and botany one of the first things we learn is that not everything looks as we might expect that it should!  Fabiana imbricata, is a member of the Tomato Family, the Solanaceae, yet, if you don’t look too close, it looks like it might belong to the Ericaceae.  At one time I was planning to take advantage of this similarity as I was attempting evoke a South African feel in part of my garden substituting this for one of the many tender South African heaths as the correct Erica species are either too tender, of borderline hardiness for my conditions or are simply difficult to come by.  It was sharing an area in the garden with Restio capensis, Eucomis spp., Melianthus spp. and others to give an impression of South Africa, not a strict species for species duplication of a community.  I didn’t quite pull it off….I’ve done much the same thing when substituting tropical looking temperate plants for the real thing when evoking a tropical feel.  It’s a matter of manipulation…a sleight of the garden hand.

Its Chilean Home and Garden Merit

Fabiana imbricata is not from South Africa, though it shares Gondwanan roots, and is endemic in Chile, occurring very frequently throughout much of its Andean range.  It is in fact identified as a ‘keystone’ species strongly effecting the composition of its local plant communities.  It can be found growing from well into the dry region of Coquimbo in the north, just south of the huge Atacama Desert, south into the wet Aysen region with its many islands and inlets south of the Lake District or Zona Sur.  The vast area stretches along much of Chile’s length which can be driven, on often tortuous mountain roads, for over 1,700 mi., stretching from the arid city La Serena to the small, rainforest town of Tortel, in the south, a distance almost 500 miles further than the drive from Vancouver, BC to Los Angeles, CA….There are not that many plant species in the world that span a similar latitudinal range with its accompanying climate differences.  As you look for this plant moving from north to south through Chile, the soils and its particular niches change along with the temperature and rainfall.  You are more likely to find this growing exposed in rocky scree in wetter regions to the south, while it tends to be more commonly found on sites more protected from the sun’s intensity and into better soils as you move into the arid and hotter north, more protected from the sun’s tropical intensity.  No surprise there, but overall this is an adaptable plant succeeding in cool rainforest to arid, desert like, conditions.  As would be expected across the more arid portion of its range fire is an important factor in maintaining the plant communities balance, riding it of other competing woody plants  and even aiding it in germination, when followed by ample winter/spring rainfall, though this is obviously not essential for its continuing survival in rainforest areas where fire is much less frequent.   This is a very adaptable species and as we live near the Pacific Coast in the northern hemisphere, which mirrors much of the range of conditions, we should be able to have success with it, if we pay attention to its cold limits.  Those away from the Pacific Coast, especially those with ‘continental’ climates or strong influences from them, will have to pay closer attention. Continue reading

Our Gardens as Teachers

 

Of all the things our gardens do for us, arguably the most important is their role as our teachers, even in winter when a temperate garden ‘rests’, its surface crust or top few feet, frozen, maybe sheltered beneath the cover of snow, or, as ours so often are, simply too cold for active plant growth, the soil wet, the rain too heavy to percolate fast enough down through its layers, without the active aid of either the direct heating of the sun or its effect on plants, through evapotranspiration, pumping water back into the air as the plants grow.  Gardens teach patience.  They encourage us to become more careful observers…to think and plan, to anticipate and prepare, to understand that there is more going on here than we can readily see…and they teach us about faith and trust in the natural world, that there is always more going on than we can see. Continue reading