Amotz Zahavi ( he, אמוץ זהבי) (August 14, 1928 – May 12, 2017) was an Israeli

evolutionary biologist Evolutionary biology is the subfield of biology that studies the evolutionary processes (natural selection, common descent, speciation) that produced the diversity of life on Earth. It is also defined as the study of the history of life for ...

, a Professor in the Department of

Zoology Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the animal kingdom, including the structure, embryology, evolution, classification, habits, and ...

Tel Aviv University Tel Aviv University (TAU) ( he, אוּנִיבֶרְסִיטַת תֵּל אָבִיב, ''Universitat Tel Aviv'') is a public research university in Tel Aviv, Israel. With over 30,000 students, it is the largest university in the country. Locate ...

, and one of the founders of the

Society for the Protection of Nature in Israel Society for the Protection of Nature in Israel ( he, החברה להגנת הטבע, ''HaHevra LeHaganat HaTeva''), or SPNI, is an Israeli non-profit environmental organization working to preserve plants, animals, and natural environments that repr ...

. His main work concerned the evolution of signals, particularly those signals that are indicative of fitness, and their selection for "honesty".

Biography

Amotz Zahavi was influenced to study zoology by the director of the zoo at Tel Aviv, Heinrich Mendelssohn. He received his

Ph.D A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

. from Tel Aviv University in 1970. He was married to

Avishag Zahavi Avishag Kadman-Zahavi ( he, אבישג זהבי; 1922 − 31 October 2021) was an Israeli professor emeritus of Plant Physiology at '' The Volcani Center for Agricultural Research'', Bet-Dagan, Israel. She is best known for her close collaboratio ...

, a biologist and a co-investigator. He died in Tel Aviv, Israel on May 12, 2017, aged 88.

Scientific career

Amotz Zahavi with wild Arabian babblers at Hatzeva

Zahavi is best known for his work on the

handicap principle The handicap principle is a hypothesis proposed by the biologist Amotz Zahavi to explain how evolution may lead to "honest" or reliable signalling between animals which have an obvious motivation to bluff or deceive each other. It suggests that ...

, which explains the

evolution Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...

of characteristics, behaviors or structures that appear contrary to the principles of Darwinian evolution in that they appear to reduce fitness and endanger individual organisms. Evolved by

sexual selection Sexual selection is a mode of natural selection in which members of one biological sex choose mates of the other sex to mate with (intersexual selection), and compete with members of the same sex for access to members of the opposite sex ( ...

, these act as signals of the status of the organism, functioning to e. g. attract mates. He expanded it with theories on honest signalling and the idea that selection would favour signals that impose a higher cost, those that are not easily cheated on. He worked in particular on the Arabian babbler, a long-lived and social bird with

altruist Altruism is the principle and moral practice of concern for the welfare and/or happiness of other human beings or animals, resulting in a quality of life both material and spiritual. It is a traditional virtue in many cultures and a core as ...

ic behaviour among unrelated individuals, not explainable by kin selection. Zahavi reinterpreted these behaviours according to his signal theory and its correlative, the handicap principle. The altruistic act is costly to the donor, but may improve attractiveness to potential mates, a form of

competitive altruism Competitive altruism is a possible mechanism for the persistence of cooperative behaviors, specifically those that are performed unconditionally. The theory of reciprocal altruism can be used to explain behaviors that are performed by a donor who ...

.Zahavi, Amotz (1990). "Arabian Babblers: The quest for social status in a cooperative Breeder", pp. 105–130 in ''Cooperative Breeding in Birds'', P. B. Stacey and W. D. Koenig (eds.), Cambridge University Press Zahavi is credited with co-developing the information centre hypothesis in 1973 with Peter Ward. The information centre hypothesis states that birds live in communal roosts primarily to gain information on food resource locations from other roost individuals. Towards the end of his life he attempted to apply his theory at the molecular scale and sought to examine for example whether the neuro-transmitter acetylcholine was selected due to its toxicity.

Awards

In 1980, The Society for the Protection of Nature in Israel, Zahavi and two other colleagues, were awarded the Israel Prize for SPNI's special contribution to society and the State, for the environment. In 2011, Zahavi received the Fyssen Foundation's International Prize for the evolution of social communication. In 2016, Zahavi received a prize for lifetime achievement from the Israel Society of Ecology and Environmental Sciences.

Published works

* * *Zahavi, A. and Zahavi, A. (1997). ''The handicap principle: a missing piece of Darwin's puzzle''. Oxford University Press. Oxford.

References

External links