| BEN |
| BOTANICAL ELECTRONIC NEWS |
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| ISSN 1188-603X |
| No. 356 February 10, 2006 | aceska@telus.net | Victoria, B.C. |
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In the first paragraph of his monograph on the Erythronium of western North America, E.I. Applegate (1935) suggested that the Erythronium of Europe, Asia, and eastern North America form a different natural group from the Erythronium of western North America. He did not elaborate on the difference. Others also have recognized the two groups, and Shevock et al. (1990) suggested they perhaps correspond to subgenera. However, the recognition of the two groups seems to have been largely intuitive, and no one has described their distinguishing characteristics.
After some 20 years of observing Erythronium in my garden, and for the last 15 years observing the reaction of ants to the fresh seeds of some Erythronium species, I can report that the principal distinguishing feature between the two groups is that the Erythronium of Europe, Asia, and eastern North America (which I will call Group 1) are myrmecochorous, that is their seeds are dispersed by ants, while the Erythronium of western North America (which I will call Group 2) disperse their seeds by a sort of catapult action when the erect capsules on tall, wiry stems are shaken by wind or a passing animal. The seeds of the Group 1 species that I have examined all have elaiosomes, that is, fleshy protuberances that are attractive to ants, while I have examined the seeds of all the Group 2 species and none have elaiosomes. It is obvious from the behavior of an ant when a fresh seed with an elaiosome is dropped close to it, that the elaiosome emits a scent attractive to the ant. It is presumed that the ant carries the elaiosome, with the attached seed, to its nest where the elaiosome is consumed.
Over the years, mainly by raising them from seed, I have acquired the bulbs of all the Erythronium of Europe, Asia, and eastern North America except E. propullans and E. rostratum, and all have produced fresh seeds for me to test with ants except those two and E. sibiricum, which has flowered, but failed to set seeds. With all the species that produced seeds, I tested the seeds immediately after the capsules dehisced with several local ant species. In all cases, ants immediately seized the seeds and carried them away, proving the species to be myrmecochorous. I obtained seeds of E. sibiricum from three different sources, and all the seeds had elaiosomes, so we can safely assume that species is myrmecochorous. Erythronium propullans is reported to only reproduce vegetatively and not to produce seeds, but a study by Pleasants and Wendel (1989) concluded that the species derived from E. albidum not over 9,000 years ago, so those two species must be very closely related, and I tested E. albidum and found it to be myrmecochorous. Parks and Hardin (1963) concluded that at some time in the distant past, E. rostratum and E. umbilicatum hybridized to produce the tetraploid species E. americanum. As I found that the seeds of the latter two species have elaiosomes which are very attractive to ants, it seems almost certain the same would be true of E. rostratum.
It is safe to conclude from all my observations over the years that all the known Erythronium species of Europe, Asia, and eastern North America belong together in a group distinguished by being myrmecochorous. As none of the species of western North America have elaiosomes on their seeds, and as I have tested the seeds of several of those species with ants, and found that ants ignore them, we can safely say that the western species form a group distinguished by not being myrmecochorous.
As we would expect, there are differences in the seeds and seed capsules of the two groups associated with their different methods of dispersing their seeds. Aside from the obvious difference of the presence or absence of elaiosomes, the seeds of the two groups differ in having different germination patterns. As that difference is extremely important to anyone growing Erythronium from seed, I will deal with it in some detail below. While testing the seeds of Group 1 species with ants, I noticed that the elaiosomes lost their ability to attract ants quite soon after they were exposed to air by the dehiscence of the seed capsule. Evidently a volatile substance produces the attractive scent, and it quickly dissipates, often within less than two hours on a warm day. To allow for this quick loss of the ability to attract ants, the seed capsules have evolved to make the seeds available to ants very quickly after dehiscence. Generally the mature capsules are held in a nodding position or may lie prostrate on the ground, and the walls of the capsules are leathery and roll back quickly to expose the seeds. In contrast, the mature capsules of Group 2 species are erect and have relatively firm walls to hold the seeds as in a cup until a sufficiently strong shake can catapult the seeds to some distance from the parent plant.
There are other characteristics which distinguish between the two groups. Group 1 species produce only one flower per mature bulb, while a Group 2 bulb may have several flowers. Also, the leaf mottling is different. All the species of Group 1 have plants with mottled leaves, though with both Erythronium sibiricum and E. mesochoreum some individual plants and perhaps some populations have unmottled leaves. The mottling in this group is formed of apparently random spots and blotches. In Group 2 there are species with mottled leaves and species with completely unmottled leaves, and two species with only a slight trace of mottling because they originated as tetraploid hybrids between a mottled and an unmottled species. The mottling in Group 2 has a somewhat symmetrical appearance, as it follows the veins of the leaf.
A few conclusions based on my observations still need to be mentioned. The actual mechanism of the attractive power of Erythronium elaiosomes needs to be studied. In general elaiosomes contain lipids which provide food for ants, but in some cases an elaiosome may contain a substance that works directly on an ant's instinct to carry an object to its nest. For example, oleic acid, which is present in the elaiosomes of at least some Trillium species, is believed to trigger the corpse- carrying instinct in ants (Lanza et al. 1992). While watching ants with Erythronium seeds, I often saw an ant carry a seed for some distance, only to drop and abandon its burden. Other ants that passed close to the abandoned seed would simply ignore it. Evidently the elaiosome on the seed had lost its attractive power. That raises two questions. If the elaiosome contained real food, rather than merely a substance that worked on the ant's instinct to carry the object, why would the ants abandon food? One also wonders why over time the elaiosomes had not evolved a longer-lasting attractive substance. I suspect the quickly-dissipated scent is actually advantageous for Erythronium. In addition to myrmecochory providing for the dispersal of seeds, it serves to prevent seeds accumulating near the parent plant in numbers that would attract birds and other seed-predators. If all the seeds collected by a colony of ants were carried to the nest, they would accumulate in the nest or in a nearby midden, and might be an even greater attraction for predators. When an ant abandons a seed part way to its nest, the elaiosome has served its purpose in an ideal way and there is a good chance the seed has been left where it can grow into a new plant.
In the process of raising Erythronium bulbs from seed so I could study the different species, I have learned that the seeds of the two subgenera need to be treated differently. The seeds of Group 2 species have evolved to withstand sitting in an open capsule, exposed to the weather, for weeks or even months. Consequently they are very durable. They can withstand a considerable amount of dehydration, and often will remain viable after being stored in a fridge for two or three years. Always, the germination process should be started in the fall so the seeds will have a period of winter coolness and will germinate early in spring. If seeds arrive in mid-winter, they should be stored in the fridge until the following fall. Group 1 seeds require a very different treatment. They are adapted to being deposited on the ground in midsummer, and consequently they require two or three months of moist warmth followed by the coolness of winter in order to germinate in early spring. To some extent those periods of warmth and coolness can be telescoped. I received Erythronium sibiricum seeds at the end of October. I gave them two months embedded in moist, sterilized sand in a room with a daytime temperature of about 22 deg. C and a night temperature several degrees cooler. Then I moved them to a fridge at about 4 deg. C. I got almost 100 per cent germination in the fridge over the period from early February to early March. If I can collect Group 1 seeds myself, I give them about a week in moderately dry conditions and then sow them outdoors where they can go through the seasons naturally. Group 1 seeds are not very durable, but with a little luck they will survive a year stored in a fridge.
During the election campaign, the Conservatives were coy about climate change. Their official platform spoke of developing a "made-in-Canada plan" to address greenhouse gas emissions, but didn't mention the Kyoto Protocol at all. Still, it's quite clear that Stephen Harper [Canada's new Prime Minister] is no fan of the agreement. Now that he's in power, could he tear it up? The answer is: not very easily. That's because the protocol sets out a timetable for backing out of the deal. A party must wait three years from the date on which the protocol entered into force before it can announce its withdrawal. Since the agreement only entered into force on Feb. 16, 2005, Canada cannot announce its withdrawal before Feb. 16, 2008. On top of that, the withdrawal would not take effect until one year after it is announced. So Canada is locked into Kyoto until Feb. 16, 2009. There may be a couple of ways around this. First, Canada could pull out of the United Nations Framework Convention on Climate Change (UNFCCC), the treaty to which the Kyoto Protocol is a protocol. A country that forsakes the UNFCCC is automatically withdrawn from Kyoto.
The UNFCCC sets out a similar timetable: There is a three-year waiting period before a party can announce its withdrawal, then another year before that announcement takes effect. Because the UNFCCC entered into force in 1994, Canada could announce its withdrawal today and then be formally relieved of both its UNFCCC and Kyoto obligations in a year.
That would be risky. Virtually every country in the world has ratified the UNFCCC, including many countries such as the United States that have spurned Kyoto. Repudiating the UNFCCC would make Canada an international pariah, with only Somalia and a handful of tiny or dysfunctional countries to keep us company. It would also cut us off from future international discussions on climate change.
The second way Canada could withdraw from Kyoto without having to wait until 2009 would be to beg all the other parties to let us go.
Under the Vienna Convention on the Law of Treaties, which governs how international agreements are interpreted, a party to a treaty may withdraw at any time with the consent of all the parties. But obtaining the consent of all 157 other parties would be nearly impossible. Why should Norway take pains to meet its emissions reduction target but let Canada off the hook? And who knows what trade-offs other countries might demand in return for their indulgence?
Whether he likes it or not, Harper is probably stuck with Kyoto for at least a few more years. So what can he do about it?
One option is to do nothing at all. More specifically, instead of trying to pull out of the protocol, Harper could just ignore it. He could pursue his made-in-Canada approach to global warming without worrying about whether that approach would actually be enough to achieve our emissions reduction target under the protocol.
And what if it isn't? Well, there would be no real penalty. Under the rules developed by the parties to the protocol, the punishment for exceeding your emissions quota in the first "compliance period" (2008-2012) is that your excess emissions are multiplied by 1.3 and then subtracted from your quota in the second compliance period. You may also be barred from participating in the emissions trading system and be forced to develop a plan to achieve compliance.
But these are hardly effective disincentives if you have no intention of participating in the second compliance period. Neither Canada nor any other country has signed on for that second compliance period. It's unlikely Harper would ever agree to it if it meant an extension of Kyoto.
This strategy may seem highly cynical. Openly flouting the protocol probably wouldn't do much for Canada's international reputation. And it certainly wouldn't bring us any closer to solving the climate change problem.
Then again, it would perhaps be more honest than the outgoing government's approach. Although the Liberals deserve credit for devising some highly creative, market-based mechanisms to reduce greenhouse gas emissions, not many of them would tell you with a straight face that their plan would have been enough to meet Canada's ambitious Kyoto target.
While Harper may find it easier to renounce Canada's Kyoto obligations than to make a good-faith effort to live up to them, simply ignoring them would be easier still. But no policy should be judged on the basis of easiness alone.
[Ian Richler is a Toronto environmental lawyer.]
The Section on Nomenclature of the XVII International Botanical Congress met in the Uni-Campus Lecture Hall C1, University of Vienna, Spitalgasse 2, Vienna, on Tuesday, 12 July 2005 at 9 a.m. and daily thereafter until Saturday, 16 July. The sessions continued until around 6.00 p.m. each day (with half hour breaks in the morning and afternoon and an hour's break for lunch), except on Saturday when the sessions concluded at the end of business, around 3.30 p.m., and were followed by the General Assembly of the International Association for Plant Taxonomy.
The Bureau of Nomenclature (see Division III of the Code) comprised the Rapporteur-general, John McNeill (Edinburgh, Scotland), appointed by the XVI Congress in St. Louis in 1999, and the following, appointed by the Organizing Committee of XVII Congress, the President, Dan H. Nicolson (Washington, U.S.A.), the Vice-Rapporteur, Nicholas J. Turland (St. Louis, U.S.A.), and the Recorder, Tod Stuessy (Vienna, Austria). In addition, five vice-presidents were appointed by the Section: Barbara Briggs (Sydney, Australia); Richard K. Brummitt (Kew, UK), Herve Burdet (Geneve, Switzerland), Walter Gams (Utrecht, Netherlands), and Paul Silva (Berkeley, USA).
The Section approved the Saint Louis Code as published as the basis of its deliberations. For the revised Code arising from this Congress (the Vienna Code, thus distinguished from the 1905 Vienna Rules), the Editorial Committee was given the usual power to alter wording, examples, or location of Articles and Recommendations in so far as the meaning was not affected, but was requested to retain the present numbering in so far as possible.
The Section adopted the now traditional procedures of requiring a 60% majority of the votes cast for any proposal to amend the Code to be accepted, and of not considering any proposal which received more than 75 per cent 'No' votes in the Preliminary Mail Ballot. In addition it approved the procedure that has been adopted since the Tokyo Congress of 1993 by which any new proposal or any attempt to debate a proposal rejected by 75 per cent of the mail ballot, would require the support of at least 5 members of the Section.
In general, the Section followed the sequence of the Code in considering the 312 proposals to amend the Code, published in Taxon between February 2002 and November 2004, of which a Synopsis, along with the Rapporteurs' comments, appeared in Taxon 54: 215-250 (February 2005). Of this 312, no less that 147 were related in some degree to orthography, 142 being in two sets of proposals by a single author. The Section identified some 20 of these proposals upon which it wished to take definitive action (usually to reject) and referred the remainder to the Editorial Committee.
Only the major topics addressed in the remaining 165 proposals are outlined here (the full list of actions on each proposal will appear in the November issue of Taxon, along with the results of the Preliminary mail ballot). Unlike at some previous Congresses few, if any, issues of major impact on the rules of nomenclature came before the Vienna Congress (but see below for two relating to fungi). The one that might have, the proposal to abandon a description in Latin as a requirement for the valid publication of the name of a new taxon, received more than 90% `No' votes in the mail ballot and was not considered further.
Probably the most conceptually fundamental decision taken in Vienna was the introduction into the Code of an entirely new concept in botanical nomenclature, although one that is well- established in zoological nomenclature. This is the provision for binding decisions on the application of the Code, in this case the interpretation of Art. 32.1(c) of the ICBN, dealing with whether or not a descriptive statement meets the requirement of that Article for a "description or diagnosis" - the so-called "nomina subnuda" situation. Previously the Code provided for rulings on whether or not two names or epithets are confusable, and, of course, on "disadvantageous nomenclatural change" in the conservation and rejection of names, but not on interpretation of the Code itself. The procedure established is the same as that for judgement on whether names or epithets are sufficiently alike to be confused (Art. 53.5) and the General Committee will probably need to establish mechanisms to ensure that proposed rulings coming from the different Permanent Committees are reasonably consistent in their interpretation of Art. 32.1(c).
In addition to this step, some clarification on what constitutes a description or diagnosis was also accepted: statements on usage of plants, on cultural and cultivation features, and on geographical origin or geological age are not acceptable, nor is the mere mention of features but not their expression. Clarification and extension of some of the rules dealing with valid publication of new combinations (Art. 33) were also accepted.
An important step was to deal, at long last, with names appearing in theses submitted for a higher degree. As soon as these ceased to be typewritten with carbon copies, or as soon as they were made available commercially by photo-reproduction, they had to be treated as effectively published under the Code as currently worded. In most countries this was not the intent of the authors and names appearing in such theses were normally published later in more regular publications. The difficulty in resolving this question arose from the fact that in some other countries, notably, the Netherlands and some Scandinavian countries, theses, to be accepted, must be produced in substantial numbers, and are intended as effectively published media. It was agreed that no thesis submitted for a higher degree on or after 1 January 1953 is considered an effectively published work, without a statement to that effect or other internal evidence (e.g. an ISBN, or a commercial publisher).
One of only two Special Committees to report to the Vienna Congress was the Committee on Electronic Publication. Both its (alternative) proposals received more than 75% "No" votes in the mail ballot, but the Section agreed to a discussion of the issues and eventually accepted a proposal arising from the work of an ad hoc group meeting during the Congress that commended publication, under certain conditions, of taxonomic novelties in electronic journals that also distributed a printed version.
A very important change in the Code, as it affects certain groups of organisms now recognized as fungi, was the extension to fungi of the provision of the second sentence of Art. 45.4, previously applicable only to algae. This deals with the names of taxa originally assigned to a group not covered by the ICBN, but which are now considered to be either algae - or now also fungi. To be accepted as validly published under the ICBN, such names need only meet the requirements of the pertinent non- botanical Code. The particular situation that triggered the proposal was that of the Microsporidia, long considered protozoa and now recognized as fungi. In addition, species names in the genus Pneumocystis (Archiascomycetes), containing important human and other mammalian pathogens, none of which were validly published under the St. Louis Code (usually because of the lack of a Latin diagnosis or description), are now also to be treated as validly published. The change may have negative effects on a few names in groups longer established as fungi such as slime moulds, labyrinthulids and trichomycetes, at least on authorship, but the numbers and importance are considered small compared with the benefits for the microsporidians and the species of Pneumosystis.
The Code has long provided for a dual nomenclature for fungi with a pleomorphic life history. Proposals to amend the article involved (Art. 59) in order to facilitate a single name for fungal taxa for which the anamorph-teleomorph relationship is known had not received support from the Committee for Fungi, but did receive documented support from a considerable number of mycologists unable to attend the Congress. Mycologists present agreed on one very significant change in Art. 59, through which, by using the epitype concept, a name, currently only applicable to an anamorph, may be applied in the future to the whole organism (the holomorph). A Special Committee to report to the next Congress was also established to address broader issues of the nomenclature of fungi with a pleomorphic life history.
The Section also agreed to the establishment of a Special Committee to report to the next Congress in 2011 on the nomenclature of cyanobacteria / cyanophyta jointly with relevant appointees from the Commission on Prokaryote Nomenclature (probably through the International Association for Cyanophyte Research).
At St. Louis, the rather ambiguous restriction on illustrations as types of names published after the type method entered the Code was clarified by prohibiting illustrations as types of names published on or after 1 January 1958, unless "it is impossible to preserve a specimen", a condition that most felt hard to define unambiguously. Many also felt that this "clarification" had had the effect of retroactively devalidating names published after 1957 with an illustration as type. It was decided that for names of microscopic algae and microfungi for which preservation of a type was technically difficult, the type might be an illustration, but that for all other organisms, names published on or after 1 January 2007 would require a specimen as type. A proposal to permit illustrations as types of names of microfossils, even although inherently rather similar to that covering microscopic algae and fungi, was not successful.
Stemming from the Report of the Special Committee on Suprageneric Names set up at the St. Louis Congress, it was agreed that the starting date for valid publication of suprageneric names of spermatophytes, pteridophytes and bryophytes (excl. those mosses already with a 1801 starting date) be 4 August 1789, the date of publication of Jussieu's Genera plantarum. This restores the original basis of spermatophyte family names in App. IIB, dating to the Montreal Congress of 1959, which had never been included in any article of the Code, and which had had to be changed in the St. Louis Code as a result of the Tokyo Congress failing to support a proposal similar to this one and the St. Louis Congress deleting a protecting footnote. The Section also established that double author citation is not justified or permitted at suprageneric ranks.
The rules determining when a rank is denoted by a misplaced term (and hence not validly published) were clarified and made more practical. This introduced the concepts of "minimum invalidity", by which only those names with rank-denoting terms that must be removed to provide the correct sequence would be considered not validly published, and of "informal usage", for situations in which the same term was used for several different non- sequential ranks; such names are to be treated as validly published but unranked. It was established that having the ranks of both order and family in a work precluded application of Art. 18.2 (and similarly Art. 19.2 in the cases of suborder and subfamily), and that sequential use of the same rank did not preclude valid publication.
The Section also agreed to a rephrasing of the rules dealing with morphotaxa, which, as defined in the St. Louis Code, covered all fossil taxa. There will now be an exception to this in that a taxon that, when first described, is indicated as including more than one part, life-history stage, or preservational state, will not be treated as a morphotaxon.
Clarification was made of several matters, already inherent in the Code, such as the fact that a name (e.g. an autonym) being validly published does not imply recognition of any particular taxonomic circumscription, and the fact that the name of a taxon of Recent organisms does not displace an earlier homonym applicable to a fossil taxon.
A proposal to extend conservation of names to all ranks (as is currently the case for rejection of names) failed to gain a 60 per cent majority, and a proposal to protect names of subdivisions of conserved families was also unsuccessful. A proposal from the floor to restrict the application of Art. 20.2 to Latin technical terms was successful, which has the practical implication that Cleistogenes (Poaceae) is established as validly published, a matter that has long been in dispute. (The replacement name, Kengia, is thus illegitimate).
The Section supported the suggestion that a glossary, strictly limited to those terms appearing and defined in the Code, be included in the Vienna Code.
Finally, with regard to Proposals, the Section devoted a very considerable amount of time - and even took a card vote - on a matter that was apparently of great consequence to some present, namely the position of the multiplication sign (x) before a nothogeneric formula or in front of a nothospecific or notho- infraspecific epithet. Eventually good sense prevailed and all attempts to rule on printing details were defeated, and it was agreed that the sign should be placed so as to express that it belonged with the name or epithet but was not actually part of it.
The reports of the Permanent Committees for Algae, Bryophyta, Fossil Plants, Fungi, Pteridophyta and Spermatophyta were received. The Report of the Committee for Pteridophyta included a recommendation that the Committee be dissolved as its work load was extremely light and none of the current members was prepared to serve as Secretary. The Congress accepted this recommendation and amended Division III.2 accordingly and renamed the Committee for Spermatophyta the "Committee for Vascular Plants", reflecting its new, wider role.
In view of the widespread interest expressed in the taxonomic community in the proposal to conserve the name Acacia with a new type, the Report of the General Committee was presented in two parts, the first, dealing with all matters except that approving Committee for Spermatophyta Report no. 55 (Taxon 53: 826-829. 2004), was approved without discussion. In the second part it was reported that the General Committee had approved the recommendation of the Committee for Spermatophyta that the name Acacia be conserved with A. penninervis Sieber ex DC., applicable to a species of the Australian subgenus Phyllodineae, as type, replacing the currently cited type, A. scorpioides (L.) W. F. Wight, universally treated as a synonym of A. nilotica, a species widely distributed in Africa. It was proposed from the floor that the decision of the General Committee be overturned. The President noted that this would require a 60 per cent majority, as this was analogous to a proposal to amend the Code, and after extensive and very well- reasoned discussion, the proposal to overturn the decision failed, gaining a vote of 247 : 203, a majority of only 54.9 per cent. Consequently the type of the name Acacia is confirmed as A. penninervis and, if the some 160 species of the former Acacia subg. Acacia are treated as a separate genus, the correct name is Vachellia, whereas the 1000 or so species of what was Acacia subg. Phyllodineae will retain the name Acacia. Regardless of the conservation proposal, adopting the recent widely accepted taxonomic splitting means that over 200 other Acacia species, some 70 in Africa, are segregated as Senegalia.
[As explained by the Rapporteur-general, in answer to a question in the final plenary session of the full Congress, the reason for the requirement of a 60 per cent% vote to overturn the decision of the General Committee was that Art. 14.14 of the Code makes clear that the de facto decision on conservation and rejection of names rests with the General Committee, in that botanists are authorized to adopt such names in the sense of the conservation, pending the decision of a later IBC, and that such names often appear in editions of the Code, prefixed by an asterisk (see, e.g. the Berlin Code - Regnum Veg. 118: 111. 1988). Whereas the Nomenclature Section has the final decision, overturning a decision of the General Committee is clearly a momentous step and, like an amendment to the Code, is not to be taken lightly.]
Nominations to the, now only seven, Permanent Nomenclatural Committees (see Division III of the Code) were approved (details have been published in the November 2005 issue of Taxon) and John McNeill was re-appointed Rapporteur-general for the XVIII Congress, which the final session of the full Congress later agreed would be in Melbourne, Australia from 24-30 July 2011 - with the Nomenclature Section presumably in the preceding days.
As usual the final plenary session of the Congress resolved that the decisions of its Nomenclature Section with respect to the International Code of Botanical Nomenclature, as well as the appointment of officers and members of the nomenclature committees, made by that section during its meetings, 12-16 July, be accepted.
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