Searching for the ancestors of lovebirds, an update
[Genus Agapornis]
Part 2
By Dirk Van den Abeele
Ornitho-Genetics VZW
Published BVA-International Magazine June 2025
Discoveries genus Agapornis
In this article we review, step by step, the discoveries through the years. As far as I have been able to trace, it was in 1969 when the first article was published that shed light on the evolutionary lineage of the genus Agapornis [1]. At that time, T.N. Pocock described a number of bird fossils from the Pleistocene in Ostrich, Journal of African Ornithology. The Pleistocene is a geological epoch and indicates the period situated between 2.588 million to about 11,500 years ago. This included two different lovebird species [1]. It was possible to determine this from the bones found.
Now, of course, one may wonder how that is actually determined from and to when each period should run. This is a very extensive process coordinated by the International Union of Geological Sciences [2], [3]. These scientists have created the ‘Geological Time Scale’ and regularly update this geological time scale at conferences. Each period is mostly characterised by environmental factors of that time, resulting in a specific layer deposition. Layers that we can clearly see from certain rock formations. Here, the dust, sand, silt deposits and plants have created millimetre by millimetre new layers of earth containing fossil remains of the environment present. Based on the age of the fossil remains in these sedimentary layers, these periods are determined.
Pocock studied fossil remains of birds excavated years before by Dr C.K. Brain in the caves of Kromdraai, Gauteng province in South Africa. The remains were recovered in pellets of – extinct – owl species that probably retreated to these caves at the time to rest or perhaps breed. Based on these fossils, he concluded that at least two diverse species of lovebirds must have been present back then. The bones found of the smallest species showed many similarities with the skeleton of a budgerigar [Melopsitacus undulatus] and was still slightly smaller in size than Agapornis roseicollis, but certainly not smaller than Agapornis lilianae. The presence of remains of hatchlings made him suspect that these birds were also breeding on site.
Some fractions of the skeleton of a second species were also found. These too were compared with the skeleton of Agapornis roseicollis and it was clear that – since these remains had been found in a different place and were clearly different from the first – they were probably a different species. It was estimated that the age of both fossil remains was around 1 million years old. This would imply that at least two species of lovebirds would have lived in north-eastern South Africa during this period. A region where lovebirds are not found today. The nearby areas where we now find lovebirds are Namibia in the west where Agapornis roseicollis lives [4], [5] and in the north Zambia where the habitat of Agapornis nigrigenis is now located [6], [7]. What these birds looked like back then we obviously have to guess.
Significantly, these findings were confirmed in 2009 and 2010 by Dr Thomas Stidham of the Faculty of Ecology and Evolutionary Biology in Texas [8], [9]. He also discovered fossil remains of birds and on closer inspection they were found to match the descriptions made by T.N. Pocock 40 years ago. Unfortunately, the reference material on which T.N. Pocock based his publication could no longer be found in the archive; the archive box appeared to be empty. Nevertheless, Dr Thomas Stidham could also conclude from these new fossils he was able to examine that at least two (extinct) lovebird species indeed lived in this region.
In 1985, US ornithologist and palaeontologist Pierce Brodkorb (1908 – 1992) published his ‘Preliminary report on Pliocene/Pleistocene birds of East Africa’ [10]. In it, he reported the results of his investigations of fossils excavated by Louis and Mary Leakey around 1940 – 1950 in Tanzania in the Olduvai Gorge and in the prehistoric Laetoli site 45 km away in Ngorongoro district. He indicated that fossils of ‘a few’ in other words ‘a pair’, presumably a twosome, of lovebird species were found. These fossils were located in a layer between 1.7 million to 700,000 years old. Brodkorb’s findings were further confirmed in 2010 by a study by Kari A. Prassack [11].
Between 1994 and 2000, palaeontological research was conducted on the habitat of Ardipithecus ramidus. This precursor of today’s humans lived about 4.4 million years ago and had been discovered shortly before in Ethiopia [12]. Naturally, this also brought out a lot of fossil remains of animals. Among them were also remains of lovebirds. These were later studied in detail and Antoine Louchart confirmed the presence of fossil extinct lovebird species in Ethiopia in 2009 [13].
In late 2010, I was forwarded a new scientific publication that reported newly discovered fossil remains of an unknown species of lovebirds [14]. Céclile Mourer-Chauviré and Denis Geraads, two French scientists examined fossils found near Casablanca, Morocco. These findings included remains of a previously unknown species of lovebird. For most, this came as a surprise since the current species of lovebirds are only found in the equatorial region and southern Africa. No one therefore expected to see an ancestor of our lovebirds emerge in northwest Africa, right on the Atlantic Ocean. Comparisons with skeletons of still existing species taught us that this species was very close in size to the current size of Agapornis taranta. As with the fossil remains found at Kromdraai, we are left guessing what these birds looked like. This (extinct) lovebird species was given the name Agapornis atlanticus by its discoverers . The sites hint that these birds probably nested in cavities in hardened sand layers in hills. And here too we see a connection with the still existing species, Agapornis pullarius, which has its contemporary habitat south of the site of these fossils, as it also digs its nest chamber in termite mounds. Coincidence or not, who knows?
In spring 2013, just under two years after scientists discovered and named fossils of Agapornis atlanticus in Morocco, another fossil of an extinct Agapornis was added to the list of extinct lovebird species. Parts of skeletons of an extinct species were discovered in the Upper Varswater rock formation of Langebaanweg, South Africa. This species was named Agapornis attenboroughi by Albrecht Manegold after Sir David Attenborough. This English natural scientist is best known to us for his wonderful nature documentaries which he makes for the BBC. What exactly the birds looked like is of course another question mark. The fact is that they were about the same size as Agapornis lilianae.
In late 2023, it is again French palaeontologist Cécile Mourer-Chauviré who reports fossil remains of Agapornis. These were found in Grillental VI, Sperrgebiet, in Namibia and are thought to date from the early Miocene, which is about 20-19 million years ago. These are then immediately the oldest remains of a species of lovebird known to date [15].
And finally, the, so far, most recent publication on extinct lovebird species dates from May 2024 [16]. Here, researchers describe a hitherto unknown (and extinct) lovebird species and named it Agapornis longipes nov. sp. The fossils were discovered in the Early Pleistocene research site of Swartkrans in South Africa. This site has been named the ‘Cradle of Humankind World Heritage Site’ because remains of an ancestor of ours were also found there. Quite a few bones of Agapornis longipes were discovered and what stands out are the rather long tarsometatarsus (walking legs). The size of the bones found indicates a small species of Agapornis, but proportionally with the longest walking legs of all known lovebird species. This extension of the legs could be related to the dietary adaptation of the extinct species, as the longer legs possibly favoured this ground feeder in the high and dense grasslands characteristic during the Plio-Pleistocene and Early Pleistocene transition. Hence the name Agapornis longipes which is Latin for long legs.
Exactly what they looked like and what colours they had, we are back to fantasising for ourselves, as no one can tell us.
As you can see, we can at least be sure that there used to be several species of lovebirds scattered across the entire African continent, and rest assured that we can only know a fraction of them. Millions of years of species formation/evolution cannot possibly be summed up by a limited number of discoveries. The oldest fossils of lovebird species are between 19 and 20 million years old, the youngest fossils of lovebirds found to date perhaps only tens of thousands of years.
Evolution goes on and on, agonisingly slow, almost invisible to the human eye. And evolution continues. Species disappear, others arise. Think of Agapornis nigrigenis, even Agapornis fischeri today is threatened in their existence and in danger of extinction, just like those species in the past.
So, as in 2011, I conclude my article with the following words: ‘One more reason to make concerted efforts to protect the still existing species in their natural habitat’.
Keep up the good work!
Dirk Van den Abeele
Ornitho-Genetics VZW
Literature:
[1] T. N. Pocock, ‘Pleistocene bird fossils from Kromdraai and Sterkfontein’, Ostrich, vol. 40, nr. S1, pp. 1-6, 1969.
[2] F. M. Gradsteina en J. G. Oggb, ‘The geologic time scale’, Timetree Life, p. 26, 2009.
[3] B. McGowran e.a., ‘Neogene and Quaternary coexisting in the geological time scale: The inclusive compromise’, Earth Sci. Rev., 2009.
[4] H. Ndithia en M. R. Perrin, ‘The spatial ecology of the Rosy-faced Lovebird Agapornis roseicollis in Namibia’, Ostrich J. Afr. Ornithol., vol. 77, nr. 1, 2006.
[5] Ndithia, Henry, Perrin, en R. Michael, ‘Diet and foraging behaviour of the Rosy-faced Lovebird Agapornis roseicollis in Namibia’, Ostrich – J. Afr. Ornithol., vol. 77, nr. 1-2, pp. 51, 45, apr. 2006.
[6] L. Warburton en M. R. Perrin, ‘Roosting requirements and behaviour of the Black-cheeked Lovebird Agapornis nigrigenis (Sclater 1906) in Zambia.’, 2005.
[7] L. S. Warburton en M. R. Perrin, ‘Nest-site characteristics and breeding biology of the Black-cheeked Lovebird Agapornis nigrigenis in Zambia’, Ostrich – J. Afr. Ornithol., vol. 76, pp. 162-174, okt. 2005.
[8] T. A. Stidham, ‘A small Pleistocene lovebird (Psittacidae: Agapornis) from Plovers Lake, South Africa’, Neues Jahrb. F 252 R Geol. Pal 228 Ontol.-Abh., vol. 256, nr. 1, pp. 123-128, 2010.
[9] T. A. Stidham, ‘A lovebird (Psittaciformes: Agapornis) from the Plio-Pleistocene Kromdraai B locality, South Africa’, Afr J Sci, vol. 105, nr. 3-4, 2009.
[10] P. Brodkorb, V. D. Ilyichev, en V. M. Gavrilov, ‘Preliminary report on Pliocene/Pleistocene birds of East Africa’, XVIII Congr. Int. Ornithol., vol. 1, pp. 174-177, 1985.
[11] K. A. Prassack, ‘Late Pliocene avifauna from the hominid-bearing Zinjanthropus land surface at Olduvai Gorge, Tanzania. In Proceedings of the VII International Meeting of the Society of Avian Paleontology and Evolution, ed. W.E. Boles and T.H. Worthy’, Rec. Aust. Mus., vol. 62, nr. 1, pp. 185-192, mei 2010, doi: 10.3853/j.0067-1975.62.2010.1541.
[12] T. D. White, G. Suwa, en B. Asfaw, ‘Australopithecus ramidus, a new species of early hominid from Aramis, Ethiopia’, Nature, vol. 371, nr. 6495, pp. 306-312, sep. 1994, doi: 10.1038/371306a0.
[13] A. Louchart e.a., ‘Taphonomic, avian, and small-vertebrate indicators of Ardipithecus ramidus habitat’, Science, vol. 326, nr. 5949, pp. 66-66e4, 2009.
[14] C. Mourer-Chauviré en D. Geraads, ‘The Upper Pliocene Avifauna of Ahl al Oughlam, Morocco. Systematics and Biogeography’, Rec. Aust. Mus., vol. 62, 2010.
[15] C. M.-C. M. Pickford, H. Mocke, en A. Nduutepo, ‘Small birds (Psittaculidae, Galliformes and Passeri) from the Early Miocene of Namibia’, 2023.
[16] M. Pavia e.a., ‘A new species of Lovebird (Aves, Psittaculidae, Agapornis) from the Plio-Pleistocene of the Cradle of Humankind (Gauteng, South Africa)’, Geobios, aug. 2024, doi: 10.1016/j.geobios.2024.05.006.