Re: [Aroid-l] Adelonema

From: Jason Hernandez <jason.hernandez74 at yahoo.com> on 2011.11.26 at 05:31:16 This discussion reminds me of something I have been wondering about for a long time.  Most books about fossils for laypersons focus on animals; the few on paleobotany tend to give a survey of the evolution of the plant kingdom as a whole.  It is very difficult to find anything bringing together the fossil record of a particular plant taxon.  If there was a small book -- even with b&w pictures, to save on printing -- on fossil Araceae, I know I would be interested.  Who else would be?  Do we have sufficient interest to be worthwhile?   Jason Hernandez Naturalist-at-Large Date: Thu, 24 Nov 2011 19:45:11 +0100 From: Lars <larsmaillist@googlemail.com> Subject: Re: [Aroid-l] Adelonema To: aroid-l@gizmoworks.com Message-ID: <4ECE90B7.2060805@gmail.com> Content-Type: text/plain; charset=3DISO-8859-15; format=3Dflowed Hello everybody, sorry for this mail coming a bit late. I wanted to add something to the discussion of the aroid biogeography but had problems posting here on the list. Well, if you can read this, it means it finally worked. Thanks Steve for figuring out the problem! I am just working on the dating and biogeography of the family for my phd. Basically, I use molecular data and assign fossil to certain nodes in order to get minimum ages for all other nodes. It also means, that I don't even have a glimpse of the deep understanding in the ecology, morphology, and taxonomy of Tom and Peter (and others), as I just work since a few years with Araceae and mainly from a molecular point of view. Having said that, here are some of my results. (The ages are minimum ages and therefore might be considerably older.) The spit between Adelonema and Homalomena is relatively young, at least 25 Ma. Maybe 40 Ma is more realistic, but I don't think it is much older. Although I would like to explain it by vicariance (maybe in a very warm period in the Paleocene, when there was subtropical climate in Antarctica and a land connection to Australia). The direction would be from South America to SE Asia, as Peter told me Philodendron is basal to the two genera in his more detailed dataset. It is very unlikely that they got dispersed over the pacific, but not impossible. There have been some weird long distance dispersals. If it would be 50-60 Ma a pathway through Antarctica and Australia could have been possible. The same young ages (20-30Ma) are in the disjunctions of the Lasioideae and Monstera (which is in a South East Asian clade). The split between Philonotion and the rest of the Schismatoglottideae on the other hand is quiet some time older, at least 45 Ma. With the error boundary and considering it as minimum a dispersal in the Paleocene might have been possible. The Bornean Nephthytis bintuluensis groups with Aglaonema and Aglaodorum (both from SE Asia), while the rest of Nephthytis groups with Anchomanes and Pseudohydrosme from Africa. The split between these two groups was at ~40 Ma. Rhaphidophora, Amorphophallus, and Arisaema went somewhen in the Miocene to Africa. Peltandra (eastern North America) and Typhonodorum / Arophyteae (Madagascar) have spilt in the Eocene and have had ancestors in Asia (good fossil record). So it must have been a relatively continuous connection, or movement later to Africa at the one side and crossing the Bering Strait at the other. The Origin of the Araceae is a bit more difficult. The ages are not really clear, as for the molecular dating with fossil assigned as minimum ages you have to have a maximum bound at the base. But they surely go back to the Early Cretaceous (fossil record), maybe even Jurassic. The true Araceae (without Lemnoids and Proto-Araceae) most probably come from Gondwana. But reconstructing the real origin it has to be taken into account the free floating (and mostly world wide distributed Lemnoids), the today probably only remnant basal Gymnostachys (Australia) and Orontioideae (Laurasia), and the Alismatales, the next sistergroup of the Araceae (many in the northern hemisphere, or marine, or sweet water plants and world wide distributed). That leaves everything open for speculation and any reconstruction there is difficult, so to answer an earlier question of Christopher: No, there is no data robust enough to give an unambiguous result for the origin (I guess that is what you mean with center of radiation). At least that is what the molecules and some modern methods let suggest. Very best, Lars (l.nauheimer@gmail.com) Am 24.11.2011 19:19, schrieb Steve Marak: > That let me see the problem. > > Aroid-L has you as "larsmaillist@gmail.com", but your posts are coming > from "larsmaillist@googlemail.com". From Google's side, the two are the > same, so you are still getting posts from the list, but from Aroid-L's > side they are different, so you can't post. > > The fix of course is to get your address changed in Aroid-L. I have tried > to do this from the administrative interface, but it has not changed. I'm > hoping this is because it has sent you a confirmation and is waiting on > your response. If not, then we can still change it, but it will require > more work. > > Steve > > > On Thu, 24 Nov 2011, Lars wrote: > >> Am 22.11.2011 10:18, schrieb Peter Boyce: >> >>        There a quite some "shared" clades for this trans ecozone distribution: >> >>          >> >>        The `obvious' ones are the Schismatoglottis Alliance [Philonotion][Cryptocoryneae+Schismatoglottideeae] >> >>          >> >>        The Monsteroideae (with notably Rhaphidophora in W Africa, and IndoMalaya) >> >>          >> >>        The Lasioids, especially Anaphyllopsis (Neotropics) Lasimorpha (W Africa), Anaphyllum (India), >>        Lasia/Cyrtosperma/Podolasia (Asian tropics) >> >>          >> >>        The extraordinary Nephthytis in West Africa&  N Borneo >> >>          >> >>        More subtly Aglaonema/Aglaodorum (Asian tropics) is compellingly linked to almost wholly African >>        Nephthytideae. >> >>          >> >>        The most `complete' clade is in American Journal of Botany 98(4), 654-668] - Cusimano et al 2011.pdf >> >>          >> >>        Peter >> >>          >> >>        From: aroid-l-bounces@www.gizmoworks.com [mailto:aroid-l-bounces@www.gizmoworks.com] On Behalf Of >>        Christopher Rogers >>        Sent: Tuesday, 22 November, 2011 1:58 AM >>        To: Discussion of aroids >>        Subject: Re: [Aroid-l] Adelonema >> >>    >> >> Thank you, Peter and Tom! >> >>    >> >> So, thinking biogeographically, am I understanding you correctly that Adelonema and Homalomena are sister >> taxa, having split roughly 75mya? Even 75 mya, these regions were never near each other. Do you think that >> these genera used to be distributed from South America, across Africa to Southeast Asia? Are there any sister >> clades in Africa for these genera or for other genus groups with a similar South American/Asian distribution? >> >>    >> >> Happy days, >> >> Christopher >> >> >> >>    >> >> On Mon, Nov 21, 2011 at 2:27 AM, Peter Boyce<phymatarum@googlemail.com>  wrote: >> >> Hi Marek, and other aroid-l folks, >> >>    >> >> Tom as nicely summed up the situation; allow me to put some more meat on the bones. >> >>    >> >>    >> >> We have two independent sets of molecular data that show convincingly that the Neotropical species currently >> assigned to Homalomena do not belong there NOR do they belong in Philodendron - as had been suggested by a >> previous study [Molecular phylogeny of the genus Philodendron (Araceae): delimitation and infrageneric >> classification - [Botanical Journal of the Linnean Society 156: 13-27] - Gauthier, Barab?&  Bruneau 2008]. >> >>    >> >> The `coarse' detail is a molecular clock study by Nauheimer et al, which gives dates the diversification of >> the Neotropical and Paleotropical clades at a minimum of ca 75 MYA. >> >>    >> >> The 'fine detail' comes from a molecular study we've done in Malaysia as part of our work on the "true" >> Homalomena species. This paper is in prep. now, a spin-off from the phylogeny work done by two of our Master's >> projects (Ng Kiaw Kiaw - who works on chemical profiling - and Hoe Yin Chen, who's working on pollination and >> floral fragrance analyses). >> >>    >> >> While Curmeria is `better known', the earliest name is Schott's Adelonema. --1742207901-149684952-1322285476=:2751-- --===============7103307950292339673==

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