In several instances, Sarfati's use of references is difficult to check for accuracy. He cites a reference that no longer exists (reference 27 gives an undated webpage that is no longer available). And he cites references to out-of-print texts not readily available online or in public libraries. Because biogeography is a rapidly changing and growing field, such references are likely to be based on out-of-date information (for example, he cites a paper from 1972 and books from 1976, 1991 and 1993).
What follows (in this blog post and a couple more) is an examination of Sarfati's arguments and references where they can be easily checked.
For example, species of cactus, which supposedly evolved in South America 30 million years ago, are also found in Africa, yet these continents are said to have separated 70 million years before. [Page 173]
Another example is the cactus, a specialized desert-adapted plant. One genus, Rhipsalis, is native to Africa, Madagascar and Sri Lanka. So did they predate the breakup of the southern supercontinent Gondwana, or were its seeds secondarily introduced by ocean-crossing birds? [Page 174]Firstly, apart from one species, all cacti are native exclusively to the Americas. The one exception is Rhipsalis baccifera, which originates in the Americas but also has a distinct subspecies found in Africa and Sri Lanka. Any species other than Rhipsalis baccifera (including other species of the genus Rhipsalis) found in Africa or Asia have been introduced there by humans. Thus, both of Sarfati's statements are misleading.
There are several theories for how Rhipsalis baccifera found its way to Africa and Sri Lanka. The leading theory seems to be distribution by migratory birds.[2] Another theory is that the seeds floated across the Atlantic.[3] And a more recent theory questions Rhipsalis baccifera’s 'native' status in Africa, arguing the plant was first carried between continents by people and then spread widely by birds.[4]
The same applies to rodents and a number of other creatures, also found on both continents [South America and Africa], yet are meant to have emerged long after the separation. [Page 173]Sarfati's reference for this statement is to a book chapter by zoologist Wilma George titled 'The strange rodents of Africa and South America', from George and René Lavocat's 1993 book The Africa-South America Connection. While I couldn’t find a copy of the book, I found another far more recent book chapter on the same topic by de Oliveira, E Molina and G Marroig.[5] The chapter references George and Lavocat's work and seeks to answer the question: "how did monkeys and rodents manage to travel across the Atlantic Ocean?"
Primates and rodents are thought to have arrived in South America between 50-20 million years ago (though young-Earth creationist don't accept this timeframe). De Oliveira, Molina and Marroig note at this time Africa and South America were not linked by land bridges, but were closer together than they are now (around 1,000 kilometres apart 50 million years ago). The authors provide evidence of islands along latitude 20◦S, which, 50 million years ago, could have stretched at least 500 kilometres into the Atlantic from the South American coast. They also note the absence of mammals from South America in the African fossil record – suggesting a one-way migration from Africa to South America. And studies of ancient ocean currents and winds suggest they strongly favoured a westward crossing of the Atlantic. This leads the authors to argue that "small or medium-sized mammals" could plausibly have traveled from Africa to South America by floating on islands of vegetation (a theory discussed by Sarfati on pages 169 and 171 of The Greatest Hoax on Earth) and then island-hopping.
Furthermore, continental drift doesn't explain disjunct species that are often found on continents that never bordered one another. For example, many plants and insects display range fragmentation across the Pacific Ocean. [Page 173]Sarfati doesn't elaborate on what the "many plants and insects" are. His references here are the defunct webpage mentioned earlier and a 1972 paper on seed plants by Robert Thorne (which I haven't been able to access). Statham's chapter gives one example from Thorne's paper – it reproduces a diagram showing the distribution of the plant genus Clethra. However, Statham provides no analysis beyond the comment: "The distribution of the plant genus Clethra, for example, is shown in figure 2." Nevertheless, further on in his chapter, Statham goes some way to answering his own (and Sarfati's) anomaly of species' fragmented distribution around the Pacific Ocean:
The potential for dispersal of plants and animals across large stretches of water by natural rafts has been accepted by evolutionists and creationists for many years....Significantly, biogeographers sometimes refer to oceans rather than continents as the main biogeographic regions. This is because, very often, patterns of disjunction are seen where many terrestrial organisms are distributed around the land bordering an ocean. So clear was this to the twentieth-century biogeographer Léon Croizat that he spent much time drawing "tracks" to chart repetitious occurrences of these patterns....From these generalized tracks, Croizat identified five biogeographic "nodes" or "gates" of plant and animal dispersal across the world.[6]Back to Sarfati:
There are many other examples where the similarities of disjunct species don't match the pattern expected by evolution and slow continental drift. For example, animals in central and southern Africa are closer to those of southern Asia than those of northern Africa. [Page 174]Actually this example matches the pattern expected by evolution and slow continental drift. Around 125 million years ago, India broke off from what is now southeast Africa and drifted north for around 75 million years until it collided with what is now Asia (creating the Himalayas). Thus at one point India and southern Africa shared the same species, which then evolved separately after the continents separated. Climatic changes 20 million years ago caused the extinction of many of the species in India. And after that mammals entered India from the rest of Asia, through passes on either side of the emerging Himalayas. However, the remnants of species of African descent were still there and the similarities between African and Indian wildlife have remained until today.[7]
Plants in Madagascar are remarkably similar to the flora of Indonesia rather than mainland Africa. [Page 174]Here Sarfati cites a paper by George Schatz.[8] The paper provides explanations, within an evolutionary framework (stretching back 120 million years), for the similarities between the flora of Madagascar and the Malay Archipelago (modern-day Indonesia). The easiest explanation to grasp is that is that there has been continuous long-distance dispersal of plants across the Indian Ocean from Indonesia to Madagascar. This is greatly assisted by prevailing winds and the Indian Ocean currents. Hence it is the flora on the east coast of Madagascar that is most similar to Indonesia's flora. The currents and winds also help to explain the interesting fact that Madagascar's first settlers came not from the African mainland, but from Indonesia.[9]
[Discussion on biogeography continued in the next post]
References:
[1] Sarfati references Statham's chapter in footnote 22 on page 173. The chapter is also reproduced in full on the Creation Ministries International website: Dominic Statham, 'Biogeography' (2010) http://creation.com/
[2] Outlined, with references to the wider literature, by Charles Davis, et al, 'High-latitude tertiary migrations of an exclusively tropical clade: Evidence from Malpighiaceae', International Journal of Plant Sciences, Vol 165, No 4 (2004), p 107; available online at: http://dash.harvard.edu/
[3] Susanne Renner, 'Plant dispersal across the tropical Atlantic by wind and sea currents', International Jounral of Plant Science, Vol 165, Supp 4 (2004), pp 23-22; available online at: http://www.umsl.edu/~renners/
[4] J Cota-Sánchez and M Bomfim-Patrício, 'Seed morphology, polyploidy and the evolutionary history of R. baccifera', Polibotánica, Vol 29 (2010), pp 107-129; available online at: http://www.herbarium.usask.ca/
[5] F de Oliveira, E Molina and G Marroig, 'Paleogeography of the South Atlantic: a Route for Primates and Rodents into the New World?', in Paul Garber, et al (eds), South American Primates: Comparative Perspectives in the Study of Behavior, Ecology, and Conservation, New York: Springer (2009), pp 55-68; available online at: http://www.academia.edu/
[6] Dominic Statham, 'Biogeography' (2010) http://creation.com/
[7] 'India, the Other Africa' (13 October 2011) http://www.krugerpark.com/
[8] George Schatz, 'Malagasy/Indo-Australo-
[9] 'Thirty lost souls: How Africa's largest island was colonised by Asians', The Economist, (24 March 2012) http://www.economist.com/node/
Thanks so much for the de Oliveria reference! It confirms what I had always assumed to be true.
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