Insular dwarfism

Insular dwarfism, a form of phyletic dwarfism,[1] is the process and condition of large animals evolving or having a reduced body size[lower-alpha 1] when their population's range is limited to a small environment, primarily islands. This natural process is distinct from the intentional creation of dwarf breeds, called dwarfing. This process has occurred many times throughout evolutionary history, with examples including dinosaurs, like Europasaurus, and modern animals such as elephants and their relatives. This process, and other "island genetics" artifacts, can occur not only on islands, but also in other situations where an ecosystem is isolated from external resources and breeding. This can include caves, desert oases, isolated valleys and isolated mountains ("sky islands"). Insular dwarfism is one aspect of the more general "island effect" or "Foster's rule", which posits that when mainland animals colonize islands, small species tend to evolve larger bodies (island gigantism), and large species tend to evolve smaller bodies.

Skeletons of Malta's extinct Palaeoloxodon falconeri, the smallest known species of elephant. Adult males measured about one meter in shoulder height and weighed about 305 kg. Females were smaller.

Possible causes

There are several proposed explanations for the mechanism which produces such dwarfism.[3][4]

One is a selective process where only smaller animals trapped on the island survive, as food periodically declines to a borderline level. The smaller animals need fewer resources and smaller territories, and so are more likely to get past the break-point where population decline allows food sources to replenish enough for the survivors to flourish. Smaller size is also advantageous from a reproductive standpoint, as it entails shorter gestation periods and generation times.[3]

In the tropics, small size should make thermoregulation easier.[3]

Among herbivores, large size confers advantages in coping with both competitors and predators, so a reduction or absence of either would facilitate dwarfing; competition appears to be the more important factor.[4]

Among carnivores, the main factor is thought to be the size and availability of prey resources, and competition is believed to be less important.[4] In tiger snakes, insular dwarfism occurs on islands where available prey is restricted to smaller sizes than are normally taken by mainland snakes. Since prey size preference in snakes is generally proportional to body size, small snakes may be better adapted to take small prey.[5]

Dwarfism vs. gigantism

The inverse process, wherein small animals breeding on isolated islands lacking the predators of large land masses may become much larger than normal, is called island gigantism. An excellent example is the dodo, the ancestors of which were normal-sized pigeons. There are also several species of giant rats, one still extant, that coexisted with both Homo floresiensis and the dwarf stegodonts on Flores.

The process of insular dwarfing can occur relatively rapidly by evolutionary standards. This is in contrast to increases in maximum body size, which are much more gradual. When normalized to generation length, the maximum rate of body mass decrease during insular dwarfing was found to be over 30 times greater than the maximum rate of body mass increase for a ten-fold change in mammals.[6] The disparity is thought to reflect the fact that pedomorphism offers a relatively easy route to evolve smaller adult body size; on the other hand, the evolution of larger maximum body size is likely to be interrupted by the emergence of a series of constraints that must be overcome by evolutionary innovations before the process can continue.[6]

Factors influencing the extent of dwarfing

For both herbivores and carnivores, island size, the degree of island isolation and the size of the ancestral continental species appear not to be of major direct importance to the degree of dwarfing.[4] However, when considering only the body masses of recent top herbivores and carnivores, and including data from both continental and island land masses, the body masses of the largest species in a land mass were found to scale to the size of the land mass, with slopes of about 0.5 log(body mass/kg) per log(land area/km2).[7] There were separate regression lines for endothermic top predators, ectothermic top predators, endothermic top herbivores and (on the basis of limited data) ectothermic top herbivores, such that food intake was 7 to 24-fold higher for top herbivores than for top predators, and about the same for endotherms and ectotherms of the same trophic level (this leads to ectotherms being 5 to 16 times heavier than corresponding endotherms).[7]

Examples

Non-avian dinosaurs

Recognition that insular dwarfism could apply to dinosaurs arose through the work of Ferenc Nopcsa, a Hungarian-born aristocrat, adventurer, scholar, and paleontologist. Nopcsa studied Transylvanian dinosaurs intensively, noticing that they were smaller than their cousins elsewhere in the world. For example, he unearthed six-meter-long sauropods, a group of dinosaurs which elsewhere commonly grew to 30 meters or more. Nopcsa deduced that the area where the remains were found was an island, Hațeg Island (now the Haţeg or Hatzeg basin in Romania) during the Mesozoic era.[8][9] Nopcsa's proposal of dinosaur dwarfism on Hațeg Island is today widely accepted after further research confirmed that the remains found are not from juveniles.[10]

Sauropods

Example Species Range Time frame Continental relative

Ampelosaurus
A. atacisIbero-Armorican IslandLate Cretaceous / Maastrichtian
Nemegtosaurids

Europasaurus
E. holgeriLower SaxonyLate Jurassic / Middle Kimmeridgian
Brachiosaurs

Magyarosaurus
M. dacusHateg IslandLate Cretaceous / Maastrichtian
Rapetosaurus

Lirainosaurus[11]
L. astibiaeIbero-Armorican IslandLate Cretaceous

Paludititan
P. nalatzensisHateg IslandLate Cretaceous / Maastrichtian
Epachthosaurus

Other

Example Species Range Time frame Continental relative

Langenberg Quarry
torvosaur (blue)
UnnamedLower SaxonyLate Jurassic / Middle Kimmeridgian
Torvosaurus

Struthiosaurus[12]
S. austriacus

S. transylvanicus

S. languedocensis
Ibero-Armorican, Australoalpine, and Hateg islandsLate Cretaceous
Edmontonia

Telmatosaurus
T. transsylvanicusHateg IslandLate Cretaceous
Hadrosaurids

Tethyshadros
T. insularisTrieste provinceLate Cretaceous

Thecodontosaurus[9]
T. antiquusSouthern EnglandLate Triassic / Rhaetian
Plateosaurs

Zalmoxes[9] (purple)
Z. robustus

Z. shqiperorum
Hateg IslandLate Cretaceous
Tenontosaurus

In addition, the genus Balaur was initially described as a Velociraptor-sized dromaeosaurid (and in consequence a dubious example of insular dwarfism), but has been since reclassified as a secondarily flightless stem bird, closer to modern birds than Jeholornis (thus actually an example of insular gigantism).

Birds

Example Binomial name Native range Status Continental relative Insular / mainland
length or mass ratio

Hawaiian flightless ibises
Apteribis glenosMolokaiExtinct (Late Quaternary)
American ibises
Apteribis brevisMaui
Cozumel curassow[13]Crax rubra griscomiCozumelUnknown
Great curassow

Kangaroo Island emu[14]
Dromaius novaehollandiae baudinianusKangaroo Island, South AustraliaExtinct (c. AD 1827)
Emu

King Island emu[15] (black)
Dromaius novaehollandiae minorKing Island, TasmaniaExtinct (AD 1822)LR ≈ 0.48 [lower-alpha 2]

Cozumel thrasher[13]
Toxostoma gluttatumCozumelCritically endangered
Other thrashers

Squamates

Example Binomial name Native range Status Continental relative Insular / mainland
length or mass ratio

Madagascar dwarf chameleon
Brookesia minimaNosy Be island, MadagascarEndangered
Madagascar leaf chameleons

Nosy Hara chameleon[16]
Brookesia micraNosy Hara island, MadagascarVulnerable
Roxby Island tiger snake[5]Notechis scutatusRoxby Island, South AustraliaUnknown
Tiger snake
Dwarf Burmese python Python bivittatus progschaiJava, Bali, Sumbawa and Sulawesi, IndonesiaUnknown
Burmese python
LR ≈ 0.44 [lower-alpha 3]
Tanahjampea reticulated python[19] Python reticulatus jampeanusTanahjampea, between Sulawesi and FloresUnknown
Reticulated python
LR ≈ 0.41, males
LR ≈ 0.49, females [lower-alpha 4]

Pilosans

Example Binomial name Native range Status Continental relative

Pygmy three-toed sloth
Bradypus pygmaeusIsla Escudo de Veraguas, PanamaCritically endangered
Brown-throated sloth

Acratocnus
A. antillensis

A. odontrigonus

A. ye
Cuba, Hispaniola and Puerto RicoExtinct (c. 3000 BC)
Continental ground sloths
ImagocnusI. zazaeCubaExtinct (Early Miocene)

Megalocnus
M. rodens

M. zile
Cuba and HispaniolaExtinct (c. 2700 BC)

Neocnus
Neocnus spp.Cuba and HispaniolaExtinct (c. 3000 BC)

Proboscideans

Example Binomial name Native range Status Continental relative
Sulawesi dwarf elephantElephas celebensisSulawesiExtinct (Early Pleistocene)
Asian elephant

Cretan dwarf mammoth
Mammuthus creticusCreteExtinct
Mammuthus

Channel Islands mammoth
Mammuthus exilisSanta Rosae islandExtinct (Late Pleistocene)
Columbian mammoth
Sardinian mammothMammuthus lamarmoraiSardiniaExtinct (Late Pleistocene)
Steppe mammoth
Saint Paul Island woolly mammoth[22][23]Mammuthus primigeniusSaint Paul Island, AlaskaExtinct (c. 3750 BC)
Woolly mammoth

Siculo-Maltese elephants
Palaeoloxodon antiquus leonardi

P. mnaidriensis

P. melitensis

P. falconeri
Sicily and MaltaExtinct
Straight-tusked elephant
(left)
Cretan elephantsPalaeoloxodon chaniensis

P. creutzburgi
CreteExtinct

Cyprus dwarf elephant
Palaeoloxodon cypriotesCyprusExtinct (c. 9000 BC)
Naxos dwarf elephantPalaeoloxodon sp.NaxosExtinct
Rhodes and Tilos dwarf elephantPalaeoloxodon tiliensisRhodes and TilosExtinct
Bumiayu dwarf sinomastodont[24]Sinomastodon bumiajuensisBumiayu Island (now part of Java)Extinct (Early Pleistocene)
Sinomastodon

Japanese stegodont[25]
Stegodon auroraeJapan and Taiwan[26]Extinct (Early Pleistocene)
Chinese Stegodon
Greater Flores dwarf stegodont[3]Stegodon florensisFloresExtinct (Late Pleistocene)
Sundaland Stegodon
Javan dwarf stegodontsStegodon hypsilophus[24]

S. semedoensis[27]

S. sp.[24]
JavaExtinct (Quaternary)
Mindanao pygmy stegodont[28]Stegodon mindanensisMindanao and SulawesiExtinct (Middle Pleistocene)
Sulawesi dwarf stegodont[24]Stegodon sompoensisSulawesiExtinct
Lesser Flores dwarf stegodont[3]Stegodon sondaariFloresExtinct (Middle Pleistocene)
Sumba dwarf stegodont[29]Stegodon sumbaensisSumba, IndonesiaExtinct (Middle Pleistocene)
Timor dwarf stegodont[24]Stegodon timorensisTimorExtinct
Dwarf stegolophodont[30]Stegolophodon pseudolatidensJapanExtinct (Miocene)
Stegolophodon

Primates

Example Binomial name Native range Status Continental relative
Nosy Hara dwarf lemur[31]Cheirogaleus sp.Nosy Hara island off MadagascarUnknown
Dwarf lemurs

Flores Man[32]
Homo floresiensisFloresExtinct (Late Pleistocene)
Homo erectus

Callao Man
Homo luzonensis[33][34]Luzon, PhilippinesExtinct (Late Pleistocene)
Modern pygmies of Flores[35]Homo sapiensFloresExtantother members of Homo sapiens
Early Palau modern humans (disputed)[36]Homo sapiensPalauExtinct (?)
Andamanese[37]Homo sapiensAndaman IslandsExtant

Sardinian macaque[38]
Macaca majoriSardiniaExtinct (Pleistocene)
Barbary macaque

Zanzibar red colobus
Piliocolobus kirkiiUngujaEndangered
Udzungwa red colobus

Carnivorans

Example Binomial name Native range Status Continental relative Insular / mainland
length or mass ratio

Japanese wolf
Canis lupus hodophilaxJapan (excluding Hokkaido)Extinct (AD 1905)
Gray wolf

Sardinian dhole
(forward)
Cynotherium sardousCorsica and SardiniaExtinct (c. 8300 BC)
Xenocyon
Trinil dogMececyon trinilensisJavaExtinct (Pleistocene)
Cozumel Island coati[13]Nasua narica nelsoniCozumelCritically endangered
Yucatan white-nosed coati

Zanzibar leopard
Panthera pardus pardusUngujaCritically endangered or Extinct
African leopard

Bali tiger
Panthera tigris sondaicaBaliExtinct (c. AD 1940)
Sumatran tiger

Javan tiger
JavaExtinct (c. AD 1975)

Cozumel raccoon
Procyon pygmaeusCozumelCritically endangered
Common raccoon

Island fox
Urocyon littoralisSix of the Channel Islands of CaliforniaNear Threatened
Gray fox
LR ≈ 0.84 [lower-alpha 5]
LR ≈ 0.75 [lower-alpha 6]
Cozumel foxUrocyon sp.CozumelCritically endangered or Extinct

Non-ruminant ungulates

Example Binomial name Native range Status Continental relative

Malagasy dwarf hippopotamuses
Hippopotamus laloumena

H. lemerlei

H. madagascariensis
MadagascarExtinct (c. AD 1000)
Common hippopotamus
Bumiayu dwarf hippopotamus[24]Hexaprotodon simplexBumiayu Island (now Java)Extinct (Early Pleistocene)
Asian hippopotamuses

Cretan dwarf hippopotamus
Hippopotamus creutzburgiCreteExtinct (Middle Pleistocene)
European hippopotamus

Maltese dwarf hippopotamus
Hippopotamus melitensisMaltaExtinct (Pleistocene)

Cyprus dwarf hippopotamus
Hippopotamus minorCyprusExtinct (c. 8000 BC)

Sicilian dwarf hippopotamus
Hippopotamus pentlandiSicilyExtinct (Pleistocene)
Cozumel collared peccary[13]Pecari tajacu nanusCozumelUnknown
Collared peccary
Philippine rhinoceros[41]Rhinoceros philippinensisLuzonExtinct (Middle Pleistocene)
Javan rhinoceros

Bovids

Example Binomial name Native range Status Continental relative
Sicilian bison[25]Bison priscus siciliaeSicilyExtinct (Late Pleistocene)
Steppe bison
Sicilian aurochs[42]Bos primigenius siciliae[25]SicilyExtinct (Late Pleistocene)
Eurasian aurochs
Cebu tamarawBubalus cebuensisCebu, PhilippinesExtinct
Wild water buffalo

Lowland anoa
Bubalus depressicornisSulawesi and Buton, IndonesiaEndangered

Tamaraw
Bubalus mindorensisMindoro, PhilippinesCritically endangered

Mountain anoa
Bubalus quarlesiSulawesi and Buton, IndonesiaEndangered

Balearic Islands cave goat
Myotragus balearicusMajorca and MenorcaExtinct (after 3000 BC)Gallogoral
Nesogoral[43]Nesogoral spp.SardiniaExtinct
Dahlak Kebir gazelle[44]Nanger soemmerringi ssp.Dahlak Kebir island, EritreaVulnerable
Soemmerring's gazelle

Cervids and relatives

Example Binomial name Native range Status Continental relative

Cretan dwarf megacerines[lower-alpha 7]
Candiacervus spp.CreteExtinct (Pleistocene)
Praemegaceros verticornis[9]

Sardinian megacerine[9]
(second from left)
Praemegaceros caziotiSardiniaExtinct (c. 5500 BC)

Ryukyu dwarf deer[47]
Cervus astylodonRyukyu IslandsExtinct
Sika deer (?)

Cervus praenipponicus (?)
Jersey red deer population[48]Cervus elaphus jerseyensisJerseyExtinct (Pleistocene)
Red deer

Corsican red deer
Cervus elaphus corsicanusCorsica and SardiniaNear Threatened
Pleistocene Sicilian deer[25]Cervus siciliaeSicilyExtinct (Late Pleistocene)

Hoplitomeryx[lower-alpha 8]
Hoplitomeryx spp.Gargano IslandExtinct (Early Pliocene)
Pecorans
Sicilian megacerine[25]Megaloceros carburangelensisSicilyExtinct (Late Pleistocene)
Irish elk

Florida Key deer
Odocoileus virginianus claviumFlorida KeysEndangered
Virginia deer

Svalbard reindeer
Rangifer tarandus platyrhynchusSvalbardUnknown
Reindeer

Philippine deer
Rusa mariannaPhilippinesVulnerable
Sambar deer

Plants

Possible example Binomial name Native range Status Continental relative

Insular elephant cacti[49][50]
Pachycereus pringleiRemote islands in the Sea of Cortez
(e.g. Santa Cruz, San Pedro Mártir)
Not evaluated
Mainland elephant cacti

See also

Notes

  1. An example of noninsular phyletic dwarfism is the evolution of the dwarfed marmosets and tamarins among New World monkeys, culminating in the appearance of the smallest example, Cebuella pygmaea.[2]
  2. Based on the heights in Fig. 1 of Heupink et al., 2011[15]
  3. Based on maximum lengths of 2.5 m for the dwarf form[17] and 5.74 m for the mainland form[18]
  4. Based on maximum Tanahjampea python total lengths (TL) of 2.10 m for males and 3.35 m for females[19] and maximum southern Sumatra python snout to vent lengths (SVL) of 4.5 m for males and 6.1 m for females[20] with SVLs corrected to TLs by multiplying by a factor of 1.127, derived from the average relative tail length (0.113) of African and Indian rock pythons[21]
  5. For nearby mainland gray foxes[39]
  6. For mainland gray foxes in general[40]
  7. Like Hoplitomeryx, Candiacervus appears to be an unusual case in that members of this genus evolved into insular species of a wide range of sizes, not only dwarf forms but also some that might be considered giants.[45][46]
  8. Hoplitomeryx is evidently quite an unusual case, because members of this genus apparently evolved into both dwarf and giant insular forms on the same island(s).[45]

References

  1. Prothero, D. R.; Sereno, P. C. (Winter 1982). "Allometry and Paleoecology of Medial Miocene Dwarf Rhinoceroses from the Texas Gulf Coastal Plain". Paleobiology. 8 (1): 16–30. doi:10.1017/S0094837300004322. JSTOR 2400564.
  2. Perelman, P.; et al. (2011). "A Molecular Phylogeny of Living Primates". PLOS Genetics. 7 (3): 1–17. doi:10.1371/journal.pgen.1001342. PMC 3060065. PMID 21436896.
  3. Van Den Bergh, G. D.; Rokhus Due Awe; Morwood, M. J.; Sutikna, T.; Jatmiko; Wahyu Saptomo, E. (May 2008). "The youngest Stegodon remains in Southeast Asia from the Late Pleistocene archaeological site Liang Bua, Flores, Indonesia". Quaternary International. 182 (1): 16–48. Bibcode:2008QuInt.182...16V. doi:10.1016/j.quaint.2007.02.001.
  4. Raia, P.; Meiri, S. (August 2006). "The island rule in large mammals: paleontology meets ecology". Evolution. 60 (8): 1731–1742. doi:10.1111/j.0014-3820.2006.tb00516.x. PMID 17017072. S2CID 26853128.
  5. Keogh, J. S.; Scott, I. A. W.; Hayes, C. (January 2005). "Rapid and repeated origin of insular gigantism and dwarfism in Australian tiger snakes". Evolution. 59 (1): 226–233. doi:10.1111/j.0014-3820.2005.tb00909.x. PMID 15792242. S2CID 58524.
  6. Evans, A. R.; et al. (2012-01-30). "The maximum rate of mammal evolution". PNAS. 109 (11): 4187–4190. Bibcode:2012PNAS..109.4187E. doi:10.1073/pnas.1120774109. PMC 3306709. PMID 22308461. Retrieved 2011-02-11.
  7. Burness, G. P.; Diamond, J.; Flannery, T. (2001-12-04). "Dinosaurs, dragons, and dwarfs: The evolution of maximal body size". Proceedings of the National Academy of Sciences. 98 (25): 14518–14523. Bibcode:2001PNAS...9814518B. doi:10.1073/pnas.251548698. ISSN 0027-8424. JSTOR 3057309. PMC 64714. PMID 11724953.
  8. "Dwarf dinosaur island really did exist, scientists claim". Telegraph Media Group. 2010-02-22. Retrieved 2010-02-26.
  9. Benton, M. J.; Csiki, Z.; Grigorescu, D.; Redelstorff, R.; Sander, P. M.; Stein, K.; Weishampel, D. B. (2010-01-28). "Dinosaurs and the island rule: The dwarfed dinosaurs from Haţeg Island" (PDF). Palaeogeography, Palaeoclimatology, Palaeoecology. 293 (3–4): 438–454. Bibcode:2010PPP...293..438B. doi:10.1016/j.palaeo.2010.01.026. Archived from the original (PDF) on 2011-07-10. Retrieved 2017-07-30.
  10. Dyke, G. (2011-09-20). "The Dinosaur Baron of Transylvania". Scientific American. 305 (4): 80–83. Bibcode:2011SciAm.305c..80D. doi:10.1038/scientificamerican1011-80. PMID 22106812.
  11. Company, J. (2010). "Bone histology of the titanosaur Lirainosaurus astibiae (Dinosauria: Sauropoda) from the Latest Cretaceous of Spain". Naturwissenschaften. 98 (1): 67–78. doi:10.1007/s00114-010-0742-3. hdl:10251/148874. PMID 21120450. S2CID 31752413.
  12. Carpenter, K. (2001) The Armored Dinosaurs. Indiana University Press, 526 pages.
  13. Cuarón, A. D.; Martínez-Morales, M. A.; McFadden, K. W.; Valenzuela, D.; Gompper, M. E. (2004). "The status of dwarf carnivores on Cozumel Island, Mexico". Biodiversity and Conservation. 13 (2): 317–331. CiteSeerX 10.1.1.511.2040. doi:10.1023/b:bioc.0000006501.80472.cc. S2CID 25730672.
  14. Parker S (1984) The extinct Kangaroo Island Emu, a hitherto-unrecognised species. Bulletin of the British Ornithologists' Club 104: 19–22.
  15. Heupink, T. H.; Huynen, L.; Lambert, D. M. (2011). "Ancient DNA Suggests Dwarf and 'Giant' Emu Are Conspecific". PLoS ONE. 6 (4): e18728. Bibcode:2011PLoSO...618728H. doi:10.1371/journal.pone.0018728. PMC 3073985. PMID 21494561.
  16. Glaw, F.; Köhler, J.; Townsend, T. M.; Vences, M. (2012-02-14). "Rivaling the World's Smallest Reptiles: Discovery of Miniaturized and Microendemic New Species of Leaf Chameleons (Brookesia) from Northern Madagascar". PLoS ONE. 7 (2): e31314. Bibcode:2012PLoSO...731314G. doi:10.1371/journal.pone.0031314. PMC 3279364. PMID 22348069.
  17. de Lang R, Vogel G (2005). The Snakes of Sulawesi: A Field Guide to the Land Snakes of Sulawesi with Identification Keys. Frankfurt Contributions to Natural History Band 25, Edition Chimaira 2005. ISBN 3-930612-85-2. pp. 23-27, 198-201.
  18. Barker, D.G.; Barten, S.L.; Ehrsam, J.P.; Daddono, L. (2012). "The Corrected Lengths of Two Well-known Giant Pythons and the Establishment of a New Maximum Length Record for Burmese Pythons, Python bivittatus" (PDF). Bulletin of the Chicago Herpetological Society. 47 (1): 1–6. Retrieved 2020-03-02.
  19. Auliya, M.; Mausfeld, P.; Schmitz, A.; Böhme, W. (2002-04-09). "Review of the reticulated python (Python reticulatus Schneider, 1801) with the description of new subspecies from Indonesia". Naturwissenschaften. 89 (5): 201–213. Bibcode:2002NW.....89..201A. doi:10.1007/s00114-002-0320-4. PMID 12135085. S2CID 4368895.
  20. Shine, R.; Harlow, P.S.; Keogh, J.S.; Boeadi, N.I. (1998). "The influence of sex and body size on food habits of a giant tropical snake, Python reticulatus ". Functional Ecology. 12 (2): 248–258. doi:10.1046/j.1365-2435.1998.00179.x.
  21. Sheehy, C.M.; Albert, J.S.; Lillywhite, H.B.; Van Damme, R. (2016). "The evolution of tail length in snakes associated with different gravitational environments". Functional Ecology. 30 (2): 244–254. doi:10.1111/1365-2435.12472.; see Table S1
  22. Schirber, Michael. Surviving Extinction: Where Woolly Mammoths Endured. Live Science. Imaginova Corporation. Retrieved 2007-07-20.
  23. The mammoths of Wrangel Island, north of Siberia, are no longer considered dwarfs. See: Tikhonov, Alexei; Larry Agenbroad; Sergey Vartanyan (2003). Comparative analysis of the mammoth populations on Wrangel Island and the Channel Islands. DEINSEA 9: 415–420. ISSN 0923-9308
  24. Aziz, F.; van den Bergh, G. D. (September 25, 1995). "A dwarf Stegodon from Sambungmacan (Central Java, Indonesia)". Proc. Kon. Ned. Akad. V. Wetensch. 98 (3): 229–241. Retrieved 2017-07-31.
  25. Sondaar, P. Y.; A.A.E. van der Geer (2005). "Evolution and Extinction of Plio-Pleistocene Island Ungulates". International Journal of the French Quaternary Association. 2: 241–256. Retrieved 2017-07-31.
  26. http://www.rhinoresourcecenter.com/pdf_files/129/1291330178.pdf
  27. Siswanto, S., & Noerwidi, S. (2014). PROBOSCIDEA FOSSIL FROM SEMEDO SITE: Its Correlation With Biostratigraphy and Human Arrival in Java. Berkala Arkeologi, 34(2).
  28. Zaim, Y. (20 August 2010). "Geological Evidence for the Earliest Appearance of Hominins in Indonesia". In Fleagle, J. G; Shea, J. J.; Grine, F. E.; Baden, A. L.; Leakey, R. E. (eds.). Out of Africa I: The First Hominin Colonization of Eurasia. Springer Science & Business Media. p. 106. ISBN 978-90-481-9036-2. OCLC 668096676.
  29. http://ro.uow.edu.au/cgi/viewcontent.cgi?article=3055&context=smhpapers
  30. Saegusa, H. (2008). "Dwarf Stegolophodon from the Miocene of Japan: Passengers on sinking boats". Quaternary International. 182 (1): 49–62. Bibcode:2008QuInt.182...49S. doi:10.1016/j.quaint.2007.08.001.
  31. "New group of dwarf lemurs may be world's rarest primate".
  32. Scientist to study Hobbit morphing, abc.net.au
  33. Wade, L. (2019-04-10). "New species of ancient human unearthed in the Philippines". Science. 364. doi:10.1126/science.aax6501.
  34. Détroit, F.; Mijares, A. S.; Corny, J.; Daver, G.; Zanolli, C.; Dizon, E.; Robles, E.; Grün, R.; Piper, P. J. (2019). "A new species of Homo from the Late Pleistocene of the Philippines". Nature. 568 (7751): 181–186. Bibcode:2019Natur.568..181D. doi:10.1038/s41586-019-1067-9. PMID 30971845. S2CID 106411053.
  35. Tucci, S.; et al. (2018-08-03). "Evolutionary history and adaptation of a human pygmy population of Flores Island, Indonesia". Science. 361 (6401): 511–516. Bibcode:2018Sci...361..511T. doi:10.1126/science.aar8486. PMC 6709593. PMID 30072539.
  36. "Ancient Small People on Palau Not Dwarfs, Study Says". National Geographic News. August 27, 2008.
  37. Mondal, M.; Casals, F.; Xu, T.; Dall'Olio, G. M.; Pybus, M.; Netea, M. G.; Comas, D.; Laayouni, H.; Li, Q.; Majumder, P. P.; Bertranpetit, J. (2016). "Genomic analysis of Andamanese provides insights into ancient human migration into Asia and adaptation" (PDF). Nature Genetics. 48 (9): 1066–1070. doi:10.1038/ng.3621. hdl:10230/34401. PMID 27455350. S2CID 205352099.
  38. Rook, L. (2008-12-31). "The first workshop on European fossil primate record (Siena and Grosseto, September 11-13, 2008) with an update on Italian studies in Paleoprimatology" (PDF). Atti Muss. Stor. Nat. Maremma (22): 129–143.
  39. Parfit, M.; Groo, M. (22 April 2020). "The uplifting tale of these tiny island foxes, nearly wiped out by disaster". NationalGeographic.com. National Geographic. Retrieved 2020-04-23.
  40. Moore, C.M.; Collins, P.W. (1995). "Mammalian Species – Urocyon littoralis" (PDF). 489: 1–7. Archived from the original (PDF) on 22 January 2012. Retrieved 16 September 2011. Cite journal requires |journal= (help)
  41. Renema, Willem (2007). Biogeography, Time and Place: Distributions, Barriers and Islands. Springer Science & Business Media. p. 334. ISBN 978-1-4020-6374-9. OCLC 228153573.
  42. van Vuure, Cis (2005). Retracing the Aurochs: History, Morphology and Ecology of an Extinct Wild Ox. Coronet Books Incorporated. ISBN 978-954-642-235-4. OCLC 472741798.
  43. van der Geer, A.; Lyras, G; de Vos, J.; Dermitzakis, M. (14 February 2011). "Sardinia and Corsica". Evolution of Island Mammals: Adaptation and Extinction of Placental Mammals on Islands. John Wiley & Sons. ISBN 978-1-4443-9128-2. OCLC 894698082.
  44. Chiozzi, G.; Bardelli, G.; Ricci, M.; De Marchi, G.; Cardini, A. (2014). "Just another island dwarf? Phenotypic distinctiveness in the poorly known Soemmerring's Gazelle, Nanger soemmerringii (Cetartiodactyla: Bovidae), of Dahlak Kebir Island". Biological Journal of the Linnean Society. 111 (3): 603–620. doi:10.1111/bij.12239.
  45. Mazza, P.P.A.; Rossi, M.A.; Agostini, S. (2015). "Hoplitomerycidae (Late Miocene, Italy), an Example of Giantism in Insular Ruminants". Journal of Mammalian Evolution. 22 (2): 271–277. doi:10.1007/s10914-014-9277-2. S2CID 16437411.
  46. van der Geer, A.A.E. (2018). "Uniformity in variety: Antler morphology and evolution in a predator-free environment". Palaeontologia Electronica (21.1.9A): 1–31. doi:10.26879/834.
  47. Kaifu, Y.; Fujita, M.; Yoneda, M.; Yamasaki, S. (15 February 2015). "Pleistocene Seafaring and Colonization of the Ryukyu Islands, Southwestern Japan". In Kaifu, Y.; Izuho, M.; Goebel, T.; Sato, H.; Ono, A. (eds.). Emergence and Diversity of Modern Human Behavior in Paleolithic Asia. Texas A&M University Press. ISBN 978-1-62349-277-9. OCLC 985023261.
  48. Lister, A. M. (1989-11-30). "Rapid dwarfing of red deer on Jersey in the Last Interglacial". Nature. 342 (6249): 539–542. Bibcode:1989Natur.342..539L. doi:10.1038/342539a0. PMID 2685610. S2CID 4343091.
  49. Wilder, B.T.; Felger, R.S. (30 September 2010). "Dwarf Giants, Guano, and Isolation: Vegetation and Floristic Diversity of San Pedro Mártir Island, Gulf of California, Mexico" (PDF). Proceedings of the San Diego Society of Natural History. 42: 1–24, see pp. 9–13. Retrieved 2020-01-05. (p. 12) The dwarfing of the San Pedro Mártir plants seems to be due to a selection for shorter individuals to survive fierce tropical storms, possible root competition in such a dense forest, and the undefined effect of high levels of nitrogen and phosphorus from the abundant guano that might stunt growth. Genetic studies have not been undertaken...
  50. Burns, K.C. (May 2019). Evolution in Isolation: The Search for an Island Syndrome in Plants. Cambridge University Press. pp. 174–177. doi:10.1017/9781108379953. ISBN 978-1108379953. OCLC 1108160200. (pp. 174-175) ... the extent to which its dwarfed stature is genetically determined, and an explanation for why insular dwarfism might be selectively advantageous, awaits additional study.
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