"The world has changed. I feel it in the water. I feel it in the earth. I smell it in the air. Much of what once was is lost, because no one now living remembers it."
Galadriel
It was 2003 and many people were thinking about these words from one of the most popular sagas at that time: The Lord of the Rings. The wait to see the conclusion of the trilogy on the big screen was coming to an end, and everyone wondered if Frodo and Sam would finally complete their mission. However, few people knew then that in 2003 another hobbit appeared for the first time in a long while, who played a fundamental role perhaps not in the history of Middle-earth but certainly in human evolution.
It all started with excavations carried out in the Liang Bua cave (Flores Island, Indonesia), where well-preserved remains of a skeleton (referred to as "LB1") were found from a species that had not been known until then: Homo floresiensis, affectionately nicknamed "the Hobbit" due to its small size.
Shortly after, in 2004, the remains of nine other individuals with similar characteristics were excavated, which demonstrated that the subject LB1 found the previous year was not a rarity but rather the first evidence we had of a possible new species (Morwood et al., 2005, p. 1012). Its most recent dating was also around 18,000 years ago, and thus contemporaneous with modern humans (Morwood et al., 2005, p. 1012). However, as research has progressed, it has been discovered that this date was incorrect, and the extinction of Homo floresiensis occurred around 50,000 years ago, coinciding with the time when Homo sapiens expanded across Asia and Australia (Sutikna et al., 2016, p. 366).
What were the characteristics of these small beings? First and foremost, as we mentioned earlier, their reduced size. They barely reached a meter in height, and their cranial capacity was around 400 cc. (Brown et al., 2004, p. 1055), similar to that of chimpanzees and the Australopithecus afarensis (the species of beloved Lucy). Additionally, alongside these individuals' remains were found stone tools and evidence of fire use (Morwood et al., 2005, p. 1012), which shows a species with quite advanced and sophisticated behaviors, similar to those of the Homo sapiens. In fact, it is attributed a brain structure quite similar, with the area associated with future planning being well-developed (Falk et al., 2005, p. 243). To this we can add that we can identify them as a bipedal species, although their way of walking would not be exactly like that of sapiens (Jungers et al., 2009, p. 81).
How does this species fit into the complex web of human evolution?
To date, it is still quite uncertain what evolutionary origin is attributed to Homo floresiensis, although we can develop three main hypotheses or factions among which the principal researchers are situated:
1. Homo sapiens "anomalies"
The remains found would actually belong to Homo sapiens, and their small size is due either to their nature as dwarfs or to some pathology affecting these beings (Aiello, 2010, p. 171). This theory is based on the work published by Jacob et al. (2006), resulting from their study applied to the original skeletal remains of Homo floresiensis, and which revealed signs that could be understood as pathological, such as facial asymmetry or underdeveloped muscles (Aiello, 2010, p. 171).
2. Development of island dwarfism from Homo erectus
There were previous evidences of a population of Homo erectus in Indonesia (not on the Island of Flores itself), and this, combined with some shared characteristics (especially in the mandibular area) led to a hypothesis that these small hobbits were descendants of an isolated erectus population. Their isolation on the island would have caused their adaptation by reducing their size to better adapt to the available resources in their environment (Aiello, 2010, pp. 169-175; Dennel et al., 2014, p. 99).
3. Discovery of a new species
The team responsible for the discovery of these hominin remains instead argues that we are dealing with the discovery of a new species. This possibly originated from an earlier and more distant ancestor than Homo erectus, close to early Homo or even linked to Australopithecus (Dennel et al., 2014, p. 99). The study of mandibles has provided support for this hypothesis, as both their morphology and characteristics analyzed in the premolars place Homo floresiensis outside the known range of variation between Homo sapiens and Asian Homo erectus (Brown and Maeda, 2009, p. 588). Another key element that supports this idea is the disposition and size of the foot bones. In them, as mentioned earlier, similarities with human feet are observed; but also a disproportionate length relative to the tibia and femur, which is more characteristic of African primates (Jungers et al., 2009, p. 81). Unfortunately, it is impossible for us to know if these feet were as hairy as those described in Tolkien's work.
But what has really made this theory prevail in the scientific landscape today over the other two is a study published in 2017 analyzing phylogenetic and/or kinship relationships of our species protagonist with seven other Homo species and three Australopithecus. The conclusion obtained was that Homo floresiensis belongs to an early lineage of the genus Homo, possibly a sister species of Homo habilis, or alternatively, a basal taxon, meaning a lineage that has evolved from its root and remained unbranched (Argue et al., 2017, p. 24).
Conclusions
The discovery of Homo floresiensis and the debate it generated only serve to highlight a reality that we must not forget at any time: what we know about human evolution is very little, and even these knowledge should not be understood as absolute truths. It is very important to develop an attitude towards research characterized by an open-mindedness toward new developments presented to us. With this, we can always provide an updated and adaptable scientific discourse to possible changes, since, to conclude again with Galadriel, "even the smallest person can change the course of the future" (or the past).
Bibliography
Aiello, L. C. (2010). Five years of Homo floresiensis. American Journal of Physical Anthropology: The Official Publication of the American Association of Physical Anthropologists, 142(2), 167-179.
Argue, D., Groves, C.P., Lee, M. S. Y. & Jungers, W. (2017). The affinities of Homo floresiensis base don phylogenetic analyses of cranial, dental, and postcranial characters. Journal of Human Evolution, 107, 107 – 133.
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Sutikna, T., Tocheri, M.W., Morwood, M.J., Saptomo, E.W., Jatmiko, Awe Due, R., Wasisto, S., Westaway, K.E., Aubert, M., Bo Li, Zhao, J., Storey, M. Alloway, B.V., Morley, M.W., Meijer, H.J., van den Bergh, G.D., Grün, R., Dosseto, A., Brumm, A., Jungers, W. & Roberts, R. G. (2016). Revised stratigraphy and chronology for Homo floresiensis at Liang Bua in Indonesia. Nature, 532 (7599), 366 – 369.
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