Talk:African Forest Elephant

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[edit] Conservation Status of forest elephants incorrect as shown

At the time of writing this comment, the conservation status of the forest elephant is shown as Endangered (EN). This is incorrect, since the conservation status ratings shown in Wikipedia are obtained from the IUCN Red List (TM)of Endangered Species, and IUCN does not at present recognize two species of African Elephant (see http://www.iucn.org/themes/ssc/sgs/afesg/tools/pdfs/pos_genet_en.pdf), and in consequence there is no separate Red List entry for the forest elephant. The correct classification would be either Vulnerable (the current Red List classification of the African elephant as a single species) or Unassessed. Could someone familiar with the graphic depictions of Red List status in Wikipedia please correct that? Thanks Pitix 16:27, 24 January 2007 (UTC)

[edit] War elephants

War elephant says that Hannibal's elephants were Forest ones. Is it confirmed? Were they natural north of Sahara? -- Error 01:48, 24 Aug 2004 (UTC)

They belonged to a now extinct species, (or subspecies) called Loxodonta (africana) pharaoensis. Dan Koehl 02:33, 24 Feb 2005 (UTC)

[edit] Species or Subspecies?

This is a funny story. In the 2001 Science article where they supposedly showed that savannah elephant and forest elephant are two distinct species, they actually presented evidence that they are one species. But they still say they are two species. Quote: "Large genetic distance, multiple genetically fixed nucleotide site differences, morphological and habitat distinctions, and extremely limited hybridization of gene flow between forest and savannah elephants support the recognition and conservation management of two African species: Loxodonta africana and Loxodonta cyclotis." -- In other words: our DNA study actually found evidence that it's one species (there is limited gene flow), but we'd rather ignore this evidence and instead say they are two different species because it's better for conservation and also makes a more interesting paper that way. As far as I know, "large genetic distance" has exactly nothing to do with the question whether they are distinct species or not... If there is gene flow between them, they probably shouldn't even be considered as different subspecies. -- Am I missing something? Chl 05:02, 23 Oct 2004 (UTC)

I suppose its a question of interpretions. In fact, the crossing between the both genus Loxodonta and Elephas is fertile, indicating it should maybe be one genus. Lately it seems DNA research slowly seems to "take" over" reg forking of species, cause with its tecnique is possible to messure genetical distance between populations. Dan Koehl 17:42, 17 May 2005 (UTC)

For species to be distinct, there needs not to be complete absence of hybridization or gene flow. In fact, hybridization between good species is not even uncommon, and such hybrids are oftern even fertile if hybridization happens within the same genus. The question to ponder is, does the hybridization occur often enough in an evolutionary timeframe that the populations in question are merging genetically? In this case, there is "extremely limited" gene flow. The genetic distance per se needs not to be indicative of species status, but it is a good supportive argument. What really counts towards species stauts is the fact that there are fixed nucleotide site differences - that's the evidence that whatever hybridization there might have been, it did not occur often enough to break the species barrier. The entire argument becomes more clear if one looks at the scenario that would have been found if the elephants were one species - namely, nucleotide divergence marginal or inconsistent.
Note also that subspecies are genetically (nearly) 100% compatible - if they meet, they will hybridize; thus all subspecies of a certain species will be either allopatric representatives or have behavioral differences (mainly found in fish - subspecies that spawn at different times of the year, although these are more correctly already becoming different speciation).
I have added the reference to the North African elephant. However, I have not found a taxonomic reference. It is not clear whether this was a subspecies or a species; I'd lean towards ssp. status, as the desertification of the Sahara isolated this population very effectively. It was definitely a distinct evolutionary entity, but I do not think the time passed since its isolation was sufficient for species status at all. Dysmorodrepanis 00:31, 14 September 2005 (UTC)
Mammal Species of the World (3rd ed) is being published later this year, and I make a strong suggestion to all folks with an interest in mammalian taxonomy to closely follow MSW's classification, and to join WP:MAM to work on divying up the work of updating our articles. - UtherSRG (talk) 11:07, 14 September 2005 (UTC)

It's likely that they'll use the two-species concept, I think. However, we shouldn't always follow them.

It's a common misunderstanding under non-biologists, and probably also under biologists, that gene flow is the most important criterion for species recognition. It is not. Some horse-donkey hybrids are fertile, but horse and donkey are certainly different species.

There are a few things that are really important for species recognition:

  1. Sympatry. If two forms occur in the same place (sympatrically), it's commonly agreed upon that they are different species. Some forms may also be recognized as separate species because they're as different as two sympatric species: Marmosops parvidens and Marmosops pinheiroi, formerly considered subspecies, were found sympatrically in Paracou, French Guiana, and Marmosops juninensis and another species of which I forgot the name were also declared separate species by Voss et al. (2001) because they were as different as the two Paracou species.
  2. Large genetic distance. If two forms differ about 18% or so in mitochondrial DNA, they're probably separate species. If two specimens of the "same" species from the same locality differ by 18% (some Echimyidae species), their conspecificity becomes even more doubtful ;-).
  3. Limited gene flow. Many forms may produce fertile offspring, although they are separate species. It's possible that humans and chimpanzees produce fertile offspring, but they're certainly not one species. As yet, many molecular biologists say that the "large genetic distance probably limits the gene flow severely", so our two species are two species.
  4. Diagnosability. Some biologists (for example Colin Groves) think that two species are separate if it's possible to diagnose them accurately. This may be a bit extreme, I think.

In conclusion, there are certainly at least two species of African elephant. Ucucha|... 13:31, 14 September 2005 (UTC)

Well argued! Holds true for any species concept too (see below) - the difference between PSC and BSC (the most popular ones by far today) is mainly that a phylo-species is currently completing speciation, and a bio-species has completely finished it. In most cases (mallards and their relatives are the most well-known example to the contrary), this means the following:
Gene flow is very limited or non-existent in both phylo- and biospecies. But in the former, reproductive compatibility is not as far advanced as an increase of gene flow would not result in the "swamping" of the distinct populations into one mish-mash over time, whereas in a biospecies, hybridization capability (including behavioral, seasonal etc factors) relative to reproductive rate is so limited that the lineages' evolutionary ways have parted forever. (The "mallardine" ducks have "always" been considered biospecies, but they are actually phylospecies) Dysmorodrepanis 21:10, 5 December 2006 (UTC)


[edit] Not so certainly

There are many definitions of species, and the one thing they all have in common is that they're ultimately definitions of convenience. In consequence, the number of African elephant species depends ultimately on what definition is adopted. Disagreements between lumpers and splitters are the bread and butter of Taxonomy - a "science" that tries to create discrete hierarchical categories in a continuum. There is no taxonomic authority that determines what species should be recognized, or what definition should be adopted, and recognition in practice depends on scientific consensus. As there is currently no consensus on how many species of Loxodonta there are (see e.g. papers published by [ Pascal Tassy and Régis Debruyne (Google search)]), the neutrality of this Wikipedia article in stating that "genetic evidence has shown that..." is rather questionable. As has been pointed out above, there is good evidence of gene flow between the two types in the wild (e.g. in Garamba National Park and North Eastern Gabon, where both phenotypically and genotypically intermediate types have been identified. Under a two species scenario, these intermediate types would be considered hybrids. The irony of this is that the conservation world tends to use the species as a unit of conservation, and hybrids have zero conservation value for the conservation community. It is for this reason that assigning species status to forest elephants may actually be counter-productive for the conservation of certain populations. This explained in a [statement (pdf - 82 kb)] on the possiblity of multiple species scenarios, issued by the [ African Elephant Specialist Group (AfESG)] of the IUCN] [ Species Survival Commission]. Incidentally, and since the AfESG - which is the Red List authority for the African elephant - does not at present recognize multiple species of African elephants, the [ 2004 IUCN Red List assessment] was performed on one species only - encompassing both forest and savanna elephants. It is also worth noting that, for CITES purposes, it does not make any difference whether African elephants belong to one, two or more species - any splitting into additional species would not affect their Appendix I listing. Having said all that, nobody disputes that forest and savanna elephants look different, play different ecological roles, and require different conservation strategies. Coincidentally, however, the distribution of forest and savanna elephants is pretty well resolved by political boundaries, with forest elephants ocurring practically exclusively in Central Africa. The recently developed [ Strategy for the Conservation of Elephants in Central Africa (pdf - 1.8 Mb, in French)] goes some way towards addressing the requirement for (sub)specific conservation approaches. --Pitix 07:29, 16 December 2005 (UTC)

Note the following: "There is no taxonomic authority that determines what species should be recognized, or what definition should be adopted, and recognition in practice depends on scientific consensus. As there is currently no consensus on how many species of Loxodonta there are (see e.g. papers published by [ Pascal Tassy and Régis Debruyne (Google search)]), the neutrality of this Wikipedia article in stating that "genetic evidence has shown that..." is rather questionable."
This means that a) it is preferrable to use relative wording like, from least strong to strongest, "suggests that the taxonomic status should be reevaluated", "indicates that... may be distinct...", "argues for ... being almost certainly distinct spp." until the split/merge has become generally accepted, and for splits with pending resolution, use eg (parentheses) around the species name as here. And it argues that b), if you really really really want to get down and dirty with systematics and taxonomy, if you take a stand and use a disputed taxon on WP, it's completely kosher - if this is not a) based on original research (i.e. what the data you and only you have sitting around at home says) and b) discussed. And this is not to say that molecular evidence, or morphological evidence, or whatnot, is superior (many molecular studies are based on probability alone and it is amazing how little biogeography, paleoclimatology etc are utilizied in these questions): A taxonomic decision gets accepted ultimately, it it is based on sound reasoning which fits in line with all available evidence, the odd personal quarrel nonwithstading. Dysmorodrepanis 21:10, 5 December 2006 (UTC)
I couldn't agree more with your suggestions, and that is precisely what I did in the general Elephant page. Also agree that these things should be discussed, and that was the original aim of my comment above, but it clearly did not stir much interest, as illustrated by the fact that, a year on, only response has been posted. Anyhow, back to elephants: if you want to get a feel for the controversy and lack of consensus in the scientific community regarding this issue, the following article is worth a read: Debruyne, R. 2005. A case study of apparent conflict between molecular phylogenetics: the interrelationships of African elephants. Cladistics 21(1), 31-50. Pitix 16:41, 24 January 2007 (UTC)

[edit] No good Loxodonta-Elephas hybrids

"I suppose its a question of interpretions. In fact, the crossing between the both genus Loxodonta and Elephas is fertile, indicating it should maybe be one genus. Lately it seems DNA research slowly seems to "take" over" reg forking of species, cause with its tecnique is possible to messure genetical distance between populations. Dan Koehl 17:42, 17 May 2005 (UTC)"
As I understand it, and as is stated elsewhere in Wikipedia (Elephant), there have been, in fact, no hybrids between African and Asian elephants that have survived for more than half a month. All were described as severely deformed and died in their infancy. In this case, the fertility question in this regard seems moot. Not effectively relevant to this whole debate, but . . . —comment added by 209.149.99.2(t/c)
Molecular data is unusable to delimit genera in elephants for one reason: unclear rate of molecular evolution. In small primates, with generation times of 1-3 years, the molecular clock has ticked away at approx 1 mutation in 100 bases in the cytochrome b gene in 500.000 years over the last few millions of yers. In turtles, it is one-eigth of that. What is known is that generation time is important, as mutations can only become fixed in lineage by passing them to offspring. What is also known is that ALL data agrees on the African and the Asian elephants and all their more recent ancestors, and their extinct populations, etc pp form 2 distinct clades sister to each other that have been basically evolving in near allopatry for all their existence. It is a matter of opinion whether one considers them genera or superspecies in one genus. Personally, I'd say genera as the morphological differences are pronounced and established (as indicated by fossils); your opinion may differ. Dysmorodrepanis 21:10, 5 December 2006 (UTC)
"Lately it seems DNA research slowly seems to "take" over" reg forking of species, cause with its tecnique is possible to messure genetical distance between populations" - this is an oversimplification (although I can only give the birds-eye view on the matter). Of course the molecular data, being newly available, forms the centerpiece of recent taxonomic papers. But good scientists take care to include morphology, behavior and other aspects of ecology, and more recently - finally! - biogeography into their interpretations.
A purely molecular phylogeny is certainly not hard science, period. The nice phylo-trees (one to three usually, one MP, one ML and one consensus) one finds are created thus: analysis of DNA sequences by software that assumes - wrongly of course, but we cannot at present do it any better - that each base has an equal chance of mutating. The result are hundreds or even thousands of phylogenies that are possible. From these, usually 2 different ones are chosen, the one that is most parsimonious overall, and the one in which each single dichotomy has the highest likelihood of being correct. These are presented, and usually accompanied by a consensus phylogeny should they not differ too much.
The problem is obvious: since each of these proposed phylogenies is based on statistical inference (as opposed to factual evidence) alone, they cannot be claimed to be more than probabilistic suggestions that need to be interpreted in the light of additional evidence. Let's suppose we have a bootstrap support of 80% for 2 very distinct genera of mammals, one from North America and one from South Africa, being sister taxa according to the molecular phylogeny. This means that the phylogeny found to be most likely by the software has, as regards this node, an 80% chance to be correct. But what is the probability that this tree is indeed not only the most likely one but the correct one? Depending on this, the likelihood of the genera's relationships being correctly represented may be less than half in fact, and that's even before long branch attraction has been considered.
In such cases, the smart scientist will turn to other data to resolve this problem. For example, considering the hypothetical genera of mammals, are fossils known than indicate even closer relatives of both from Europe or South America which have become extinct in the meantime? Also, molecular data can be reinterpreted; for example in woodcreepers, morphological phylogenies placed much emphasis on the bill shape. But this is long known to be unreliable; it works in Hawaiian honeycreepers, but it does not work well in Darwin's finches. The molecular data indeed indicates that bill shapes are unreliable phylogenetic characters in woodcreepers too - but that some subtle characters of the plumage, such as whether there are spots or streaks on the breast, are an excellent indicator of relationships...
As always in science, data does not lie. It is the interpretation of data that does. If phylogenies disagree, odds are that characters in at least one of them have been misinterpreted. The spectacular paper allying the dodo with the Nicobar Pigeon, for example, presents a phylogeny that is based on molecular characters entirely. However, this is at odds with that has by now become the consensus phylogeny - based on molecular data, biogeography, and morphology - of pigeons. Conclusion? The Nicobar pigeon may or may not be the dodo's closest living relative; both indeed belong belong to an Indian Ocean radiation of pigeons, but where to place them exactly is not resolvable robustly by the available data.
This is not to be considered a critique of molecular phylogenetics per se - the addition of molecular data is perhaps the most ground-breaking event in systematics since phenetics was done away with. But as said above, all the primary data must fit. That two taxa have similar DNA sequences in some 100 bases analyzed does not imply that they are closely related; it merely makes it more likely than not that they are, but if this is contradicted by other evidence, this must be discussed. It cannot be simply assumed that the molecular data is "more correct" than other, and good scientists are aware of this. Dysmorodrepanis 16:09, 6 December 2006 (UTC)

[edit] Merge request

Requested merge: African Pygmy Elephant -> African Forest Elephant.

Justification: APE article is stub, AFE article is stubby. APE has been fairly unequivocally shown to be a clearly recognizable morph of AFE, occurring naturally under certain not quite well researched ecological conditions. AFE is a species with bimodal size variation in each sex, with transitional specimens between morpha typica and morpha pumilio being rare but apparently (as evidenced by specimens hard to assign to either) exist, and together with small size of subpopulations of pumilio ensure that the latter cannot become isolated enough to be maintained as a distinct lineage. Note this does not exclude possibility of pumilio having once been a phylo-species at least, eg a Congo Basin isolate of a common ancestor, but the overall pattern of specimens, distribution, field data, and molecular analyses suggests they are not even a subspecies yet. Think peppered moths rather. Dysmorodrepanis 21:10, 5 December 2006 (UTC)
I think the African Pygmy Elephant is not about a taxon, but merely historical. It is about a species that has once been thought to be in existance. I agree that the article might be improved, though. Ucucha 16:30, 6 December 2006 (UTC)
They are cryptids. Try merging Bigfoot into ape and you'll run into much the same problem. Merging into Pygmy Elephant would make a great deal more sense, since most of the creatures in that article are also cryptids. I'm putting on some more tags. Mermaid from the Baltic Sea 07:44, 3 January 2007 (UTC)
No the APE is not a cryptid nor a species (it is a taxon that is a junior synonym at species rank). There is no reason nowadays to assume that it is anything other than a legit morph/environmental variation of the AFE. Several verified specimens exist, and the morph at least some decades ago was alive and kicking (and there is no really good reason to suppose that the conditions which lead to diminutive size in the AFE are absent nowadays).
Try the Comptes Rendus paper which shows that the APE specimens - IIRC the type specimen namely - are indistinguishable from AFE as regards population genetics. Thus the correct taxonomy of the APE would be Loxodonta cyclotis morpha pumilio. The Indian "pygmy elephants" are cryptids bordering on "merely" little-known animals (the difference is that cryptids are unsupported by good material evidence).
Though the references from APE need to go into Pygmy Elephant. Overall I think it is best to merge Kallana into the Pygmy Elephant article (since it is at present a fairly well-documented cryptid), and merge the APE article into both Pygmy Elephant (what is not already in there) and (as a separate section) into AFE, and add Loxodonta pumilio to the synonymy of cyclotis.
Read the Comptes Rendus paper but bear in mind that APE and AFE have been documented not to mix; reconciliating both lines of evidence will make the matter entirely clear. Dysmorodrepanis 11:01, 4 January 2007 (UTC)
You're confused about the definition of a cryptid. Cryptids include animals known to be real that are argued (by cryptozoologists) to be a separate species or subspecies but are not thought so by actual biologists. What can be proven about them has no bearing on their status as cryptids, since that status only has to do with what cryptozoologists say about them. Mermaid from the Baltic Sea 18:23, 4 January 2007 (UTC)
As regards the "known animal, unknown taxonomic status", we (biologists) refer tho these as "disputed [species, subspecies]; they are certainly not prominent in the cryptozoological literature I have read (which is quite a lot for someone specializing in traditional zoology). Nobody will keep you from considering them "cryptids", but Forte would disagree. The Martinique Amazon (Amazona martinica) on the other hand is a tried-and-true cryptid, but has not been treated a lot in that literature but rather by "proper" zoologists. There are many such forms, notably the Marquesas Swamphen.
In any case, have you read Debruyne et al, and the Böhme/Eisentraut and Noack papers from here? I have, and the inevitable conclusion is that there is a diagnosable entity "African Pygmy Elephant", which cannot be diagnosed as a species by molecular phylogenetics however; mtDNA indicates that there has not been a distinct APE evolutionary lineage for quoite some time, probably never. It is essential to read at least the 3 more recent papers to get a proper understanding of what's going on here (the 2003 study does not discuss the Böhme/Eisentraut work which I was very lucky to get my hands on), but the APE is not a cryptid by any reasonable degree anymore. I could give you a discussion of the whole stuff, geographical population structure, bootstrap value analysis, evolutionary scenarios etc, but that would better go to the page.
The best analogy as regards other lifeforms is either the Peppered Moth as mentioned above, or the Mariana Mallard if one assumes the AFE and APE were briefly separating into distinct species but then merged back into one gene pool e.g. at the start of the Holocene.
What about Kallana? Merge -> Pygmy Elephant and link from brief discussion under Asian Elephant? Dysmorodrepanis 21:40, 4 January 2007 (UTC)

[edit] Moved article back to "African forest elephant"

I've moved this article—again—to "African forest elephant". The previous capitalization is just plain wrong. Neither of those words is a proper noun. This is in keeping with the standard practice here. Please don't move the article back again. +ILike2BeAnonymous 22:26, 30 January 2007 (UTC)

See WP:BIRD for the rationale of why species names are capitalized on Wikipedia. - UtherSRG (talk) 02:53, 31 January 2007 (UTC)

[edit] Paper concerning genetics of pygmy elephants

Add the reference below to the References section:

Debruyne, R., Holt, A. van, Barriel, V. & Tassy, P. 2003. Status of the so-called African pygmy elephant (Loxodonta pumilio (NOACK 1906)): phylogeny of cytochrome b and mitochondrial control region sequences. Comptes Rendus de Biologie 326(7):687-697. —The preceding unsigned comment was added by 72.194.116.63 (talk) 02:27, 12 February 2007 (UTC).

[edit] IUCN Red List Status

The IUCN Red List Status of this article is not according to IUCN/SSC, who has faild to include this species (perhaps because it is still not fully recognized as a species of its own). Thus the correct status is NE (Not Evaluated)! Tbjornstad 10:22, 8 August 2007 (UTC)

[edit] Size

I was interested to know, how the size of Loxodonta cyclotis compares to L. africana, but there were no measurements in the article. Here's a useful link, if someone's interested in correcting this fault. The fact that L. cyclotis was considered conspesific with L. africana until recently is probably the reason why there appears to be little data on the subject. --Anshelm '77 (talk) 16:04, 31 March 2008 (UTC)