Insectivory in Geladas

Thought I'd share this interesting observation about desert locust outbreaks in the Guassa Plateau, Ethiopia.  Fashing et al. (2010) observed that geladas (Theropithecus gelada), Ethiopian wolves (Canis simensis) and thick billed raven (Corvus crassirostris) feast on locusts in large quantities during an outbreak and immediately after in the Guassa Plateau. Although geladas are highly specialized herbivores, the observation suggest a surprisingly flexible diet shift during these outbreaks.

I tried to access the article but unfortunately it is paid-only. (Thank you Michelle, from Spider Monkey Tales, for a copy of the article). Judging from the abstract, it seems that this observation was done only during the locust outbreak of June 2009. It would be interesting to conduct a continuous study of this phenomenon to see if this diet shift really is a trend, like the authors suggested.

Reference:
Fashing, PJ. Nguyen, N. Fashing, NJ. 2010. Behavior of geladas and other endemic wildlife during a desert locust outbreak at Guassa, Ethiopia: ecological and conservation implications. Primates Retrieved April 19, 2010, from http://www.springerlink.com/content/w34871337p7070l1/ DOI:10.1007/s10329-010-0194-6

Contagious Yawning in Geladas

Over at Beast Ape & The Bleeding Heart Baboons blog, Beast Ape discusses about contagious yawning in geladas.

This research suggests that the yawning contagion is associated with the ability to attribute mental states to others (and possibly empathy). Among non-human mammals, contagious yawning has been demonstrated in chimpanzees (Pan troglodytes), stump-tailed macaques (Macaca arctoides), and domestic dogs (Canis familiaris).

Read more about that blog post here.

A Cross-Species Comparative Study: Grooming Patterns in Captive Populations of Hamadryas Baboons and Geladas

This is the thesis that I've been working on for the past year. Finally got it graded and I am really happy about the thesis. After writing this thesis, I have more follow-up questions pertaining to grooming than I had started with so I guess it's a good thing.

Thanks to Dr. Larissa Swedell for supervising my thesis. Also, thanks to Dr. Sara Stinson and Dr. Ekaterina Pechenkina for reading the thesis and your inputs.

Abstract:
Primates groom themselves (autogrooming) and each other (allogrooming) for a variety of purposes. Allogrooming is arguably an altruistic behavior, and may be explained by kin selection. The purpose of this study is to better understand the grooming patterns of captive hamadryas baboons (Papio hamadryas hamadryas) and geladas (Theropithecus gelada) within the context of kin selection theory, which posits that kin will interact, especially in altruistic ways, more than non-kin.

This study hypothesizes that grooming patterns in hamadryas baboons and geladas can be explained by the patterns of philopatry, dispersal, social system and bonding that are seen in wild populations. The results of this study show that there is a higher frequency of allogrooming than autogrooming in both hamadryas baboons and geladas. It also shows that gelada leader males groomed their females more than hamadryas leader males groomed their females, which does not support the hypothesis of this study. The following results showed a trend but were not statistically significant enough to support the hypotheses: female hamadryas baboons and geladas groomed more than male hamadryas baboons and geladas; hamadryas leader males groomed their females more than females groomed among themselves in the same hamadryas group; gelada females groomed each other more than gelada leader males and their females; male hamadryas baboons groomed more than male geladas; female geladas groomed more than female hamadryas baboons; hamadryas baboons groomed more than geladas.

In addition, this study also hypothesizes that there is a correlation between grooming frequency and temperature. There is a positive correlation between grooming frequency and temperature in hamadryas baboons but a negative correlation in geladas.

A Cross-Species Comparative Study: Grooming Patterns in Captive Populations of Hamadryas Baboons and Geladas

Whose hand is this?

What Is A Papio?

Prancing what? That is not a misspelled Spanish word, I did not intend for this blog to be named Prancing Papi. So, what really is a Papio?

Papio is a genus; all baboons belong to the genus Papio. Previously, Gelada, Mandrill and Drill were also grouped into the same genus but they now have their own separate genera. Gelada belongs to the genus Theropithecus while Mandrill and Drill belong to the genus Mandrillus. Gelada, Mandrill, and Drill are still colloquially referred to as baboons.

Currently the genus Papio has 5 recognized members. There are disagreements among scientists whether Hamadryas baboons are a separate species while the other four are subspecies or they all represent 5 different species of the same genus. You will see that Hamadryas baboons are listed as either Papio hamadryas or Papio hamadryas hamadryas.

Based on the biological species concept, I consider all 5 members of the genus Papio to be a subspecies of Papio hamadryas because they can reproduce and produce virile offspring hybrids. The closer the range of two baboon species, the higher the frequency of interbreeding is. This zone is sometimes call the hybrid zone. According to the ecological species concept, however, I consider all 5 members of the genus Papio to be 5 different species. So, depending on what your species concept is, there are different ways to classify them. How would you classify them and why?

The 5 Papio species are:

• Chacma Baboon, Papio ursinus (found in southern Africa).
• Guinea Baboon, Papio papio (found in the far western Africa).
• Hamadryas Baboon, Papio hamadryas (found in the Horn of Africa and south-western Arabia).
• Olive Baboon, Papio anubis (found in the north-central African savanna).
• Yellow Baboon, Papio cynocephalus (found in south-central and eastern Africa).

Male Hamadryas baboon (Papio hamadryas), The Prospect Park Zoo.

Hamadryas (Papio hamadryas) females. The Prospect Park Zoo.


Female Hamadryas and Olive baboon hybrid (Papio hamadryas x Papio anubis) The Prospect Park Zoo.

Geladas and Hamadryas: A Comparative Study Of Grooming

I'm currently working on a Senior Honors Thesis before I graduate this Spring. It's a comparative study of grooming between gelada baboons (Theropithecus gelada) and hamadryas baboons (Papio hamadryas hamadryas). This study is being done in The Prospect Park Zoo and The Bronx Zoo (Both are Wildlife Conservation Society Parks). Prospect Park Zoo houses a troop of hamadryas baboons indoors while gelada baboons can be found in an outdoor exhibit at The Bronx Zoo.

I will write about how my research is progressing on this blog, along with news and articles related to primates and hominins.

Below are some pictures of my focal animals.