R 2 and 12 years, respectively. First encounters in the elephants have been observed and recorded by scan sampling. The parameters measured have been (a) signs on the characteristic 9-PAHSA-d9 Purity Greeting Ceremony, (b) distance for the fence separating the elephants throughout 1st get in touch with, and (c) time till trunks touched for the first time. The information were statistically analysed with SPSS. The results showed that related elephants performed a complete Greeting Ceremony on reunifications. Unrelated elephants only expressed a minor greeting. Throughout 1st encounters, associated elephants predominantly showed affiliative behaviour (p = 0.001), while unrelated elephants expressed additional trans-4-Carboxy-L-proline References agonistic behaviour (p = 0.001). The distance towards the fence was drastically smaller for associated elephants than for unrelated elephants (p = 0.038). very first make contact with of trunks occurred on typical following 3.00 s. in connected elephants and 1026.25 s. in unrelated elephants. These findings indicate that connected elephants recognise their kin right after as much as 12 years of separation, meet them using a full Greeting Ceremony through reunification, andPublisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.Copyright: 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access post distributed under the terms and circumstances of the Creative Commons Attribution (CC BY) license (licenses/by/ 4.0/).Animals 2021, 11, 2990. ten.3390/animdpi/journal/animalsAnimals 2021, 11,2 ofseek contact towards the associated elephant, although unrelated elephants are hesitant throughout unifications with unfamiliar elephants and express additional agonistic behaviour. The results testify that zoo elephants show the exact same species-specific social behaviour as their conspecifics inside the wild. Additionally, it confirms the cognitive abilities of elephants along with the significance of matrilines for breeding programmes. Keywords and phrases: African elephant; zoo elephants; unification; reunification; communication; behaviour; Greeting Ceremony1. Introduction 1.1. Elephant Communication 1.1.1. Greeting Ceremony Known to become hugely sensitive mammals having a complex social structure and extraordinarily developed ways of communication, elephants and their behaviour have already been a frequent subject of research . Even so, it is primarily olfactory  and auditory [4,139] communication that has been investigated . Although sexual and breeding behaviour and communication are well-represented , the so-called Greeting Ceremony  with its huge olfactory, visual, tactile, and acoustic aspects is investigated poorly for ex situ living African elephants, so far. Although elephants generally greet other elephants by flapping their ears, lifting the head, and often touching the head on the other individual with their trunk (known as Tiny Greeting) , the Greeting Ceremony is much extra complex and typically restricted to interactions among closely connected elephants . The ethogram in Table 1 shows the behavioural things that form the Greeting Ceremony [7,18,281].Table 1. Behaviour expressed in the course of a Greeting Ceremony. Item Running towards elephant Clicking tusks and entwining trunks collectively Touching trunk Folding, lifting, spreading, and flapping ears Raising head Opening mouth Touching head Spinning round Lifting tail Acoustic signals Defecating and urinating Glandular secretion Behaviour Elephants run towards the elephant they intend to greet. Elephants click tusks and entwine their trunks.