#ElephantTuesdays: Male or female? 🐘

The sexual dimorphism is a condition that some species have when the two sexes show different characteristics. In some animal species, these differences can be very obvious (for example in Mandrills), being manifested by color, size, presence of certain features like breasts, etc.

In the case of African elephants, however, the sexual dimorphism is unfortunately not so clear. Even sometimes for the most trained eyes it can be tough to tell the gender. Even the genitals can be misleading as both penis and vulva hang ventrally. Besides, the male´s testes are located in the abdominal cavity, which makes the assumption even harder.

There are cases when the sex is more than evident: 

but If you don´t get to see an elephant erect, here are some very general tips that will help tell an African elephant´s gender apart.

Overall body shape: Males are more robust and in general bigger than females.

Head: an adult male´s head (forehead) is usually wider than an adult female´s.

Trunk: an adult male´s trunk is pretty thicker/wider than a female´s, especially the base of the trunk.

Tusks: usually longer and thicker in males than in females; a broken tusk might be as well the result of a fight between males.

Breasts: adult females have two breasts between their forelegs: 

As a curiosity: again Can, our African forest elephant in the Abidjan zoo, was thought to be a male for 20 years!!, until we saw her urinating; when males urinate, the penis comes out and then you have a good chance to claim the sex; 

Can urinating:

male urinating: 

 Original video: ACP000ciji

References:
Elephantvoices: https://www.elephantvoices.org/component/content/article/139-elephantvoices/education/807-how-to-sex-african-elephants.html

#ElephantTuesdays: Elephant species 🐘

 Although there used to exist species of elephants on earth, we can unfortunately confirm three occurring currently in Asia and Africa:

Elephas maximus (Asian elephant)

Loxodonta africana (African bush elephant)

           Loxodonta cyclotis (African forest elephant)

Sometimes it might appear easy to distinguish between all three species, or at least between the African and Asian sp., but actually it can be sometimes tricky. If you have a look at the following table, you will notice that in general, African sp. are a bit bigger and heavier than their Asian relatives. But if you are not in Asia or Africa, but in front of an elephant far from their natural habitat (like a zoo) this feature alone can be confusing, as it obviously depends on the individual´s age and physical condition. So one thing that usually helps is the size of their ears, and their head´s shape. In African elephants, their ears reach up over the neck, and the head shape is basically round.

The main morphological differences between the African and Asian elephant species are:

	Loxodonta sp.	Elephas maximus
Weight	4.000-7.000 Kg	3.000-6.000
Height (shoulder height)	3-4 m.	2-3,5 m.
Skin	wrinkled	Relatively smooth
Ears	Bigger	smaller
Tusks	Existing in both sexes	Females have no tusks or only rudimentary
Trunk	2 fingertips/ very wrinkled/more flexible	1 fingertip/less wrinkled/less flexible
Shape of the back	Concave	Convex (sometimes even straight)
Toenails	Forelegs: 4 (sometimes 5) Hind legs: 3 (sometimes 4)	Forelegs: 5 Hind legs: 4 (sometimes 5)
Belly shape	slopes diagonally downwards towards its hind legs	Round/straight, horizontal
Head shape	round	Two bulges

Interesting as it might be, yet our concern here is not about how to differentiate between African or Asian ele. but how to tell apart the two African species.

Just a short summary of physical African elephant traits:

	Loxodonta africana	Loxodonta cyclotis
Weight	4.000 - 7.000 Kg	2.000 - 4.500 kg
Height (shoulder height)	3-4 m.	2 - 3 m
Skin	wrinkled/ less and shorter hairs	Smoother/long hairs, long eyelashes
Ears	cuts usually are individual; the older they get, the more folded the ear can be shape of the African continent	cuts usually are individual; the older they get, the more folded the ear can be  round
Tusks	both sexes males have stronger ones usually curved, thicker	both sexes males have stronger ones more or less straight downwards, thinner
Trunk	2 finger tip	2 finger tip
Toenails	Forelegs: 4 Hind legs: 3	Forelegs: 5 Hind legs: 4

Asian elephant:

 African bush elephant (Source):

African forest elephant:

Original videos: ACP00022ho, ACP0002cpg

But these are only numbers and approximations, necessary when it comes to taxonomy, but in nature things don´t always work that way; in fact, there´s been controversy between taxonomists when claiming differences between both African species. 

 As a curiosity: years ago, local people and hunters, claimed to exist another species of elephants occurring in Africa, the Pygmy elephant. There was some controversy about this fact, some researchers agreed, some didn´t, and years later those individuals that were seen and thought to be pygmy elephants, happened to be the infants of the African forest species, so the new “discovery” was finally rejected. 

We have been often asked if there is a difference in behavior between all three species, and honestly, we are never really sure what to say. There are plenty of different opinions: some believe that Asian elephants are thought to be more docile than the African species, others don´t; the Africans are thought to be a bit more “dirty” than the Asians (they like to take their own poo and put it on their backs). It is also said that the African forest elephants tend to accumulate food on their backs, while the African bush elephants don´t do it that often… and we have witnessed it: see what the lovely forest elephant Can from the Abidjan zoo likes to do with her food:

Call them what you will, we personally don´t mind if they have big or small ears, thin or thick tusks, if they are clean, dirty, docile or fierce… 

THEY ARE ALL AMAZING AND INTERESTING CREATURES IN ALL THEIR VERSIONS. 

References: 
Kalinga Animal Shelter: http://www.kalinga.eu/page/de/home/index.html 
Upali: http://www.upali.ch/differences_en.html

#ElephantTuesdays: An elephant´s role in nature 🐘

Elephants are fascinating creatures. It´s no wonder that only a short 15-second video brings up interesting questions about their behavior, biology and nature.

The answers happened to be of interest, and this took us to think that it might be good to share them with all the C&S users.

This is a citizen platform focused mainly on chimpanzees, but when it comes to conservation, one cannot study a single species ecology without a general approach, and taking other related species into account.

ELEPHANTS´ ROLE IN NATURE

African elephants are listed on Appendix I of CITES (Convention on International Trade in Endagered Species of Wild Fauna and Flora) - although some States transferred back to Appendix II with specific annotations - and classified as Vulnerable on the IUCN  (International Union for Conservation of Nature) Red List of Threatened Species. Like chimpanzees, the African elephants are considered “flagship species”, that is, iconic species that provide a focus for raising awareness and action to fund broader conservation efforts.

They play a vital role in maintaining their ecosystems. They are also regarded as “keystone species” because of their important ecological role and impact on the environment, helping to open up forest clearings and distribute seeds. They can provide water for other species by digging holes in dry riverbeds and may help create paths between forest patches which can act as firebreaks and are often used by chimpanzees (and other animals) to travel.

Elephant path:

chimp on elephant path: 

Original videos: ACP000027g , ACP000023w

Besides, their footprints form natural mini puddles that form new habitats for some small aquatic species; Wolfram Remmers at the University of Koblenz in Germany, surveyed 30 such prints in the swamp forests of Kibale National Park, Uganda, over a three-day period in 2014. He and his colleagues found over 60 species, including beetles, spiders, worms and tadpoles.

Seed dispersal.

Elephants are known to be `seed dispersers´, as they disperse seeds by eating them, transporting them, and then spreading them through their dung. The overall body size of an elephant and their highly frugivorous diet make them particularly impressive seed dispersers. They are also responsible for spreading seeds in very long distances. There are some plant species which depend entirely on elephants for their dispersal. For example, in Uganda, the seeds of a plant called ‘Balanites Wilson’ are completely dependent on savannah elephants to consume and disperse their seeds, as no other animals perform this function. This particular ability allows for the rejuvenation of some habitats.

Importance of elephant dung

After seeds are dispersed by elephants, their dung provides a suitable germination environment in which seeds can grow, as it is extremely rich in minerals and fiber. It is also important in nutrient cycling, as dung provides rich nutrients to soils, acting as a great fertilizer.

Elephant dung also provides food for other species of birds, mongooses, monkeys and insects like beetles, that roll balls of dung and bury them to store as a food supply for their larvae. Others like small birds and mammals can consume undigested material from the dung, sometimes acting as secondary seed dispersers.

Not only does dung provide food for other species, but it also provides a suitable habitat for them, in a way that a dung pile could be a small ecosystem in itself. For example, many invertebrates including beetles, ants, centipedes, millipedes, scorpions, crickets, spiders and termites are found living in dung. These invertebrates will then be used as food source by other vertebrates like jungle fowls and monitors.

As a curiosity, the elephant poo is also used to make paper, widely advertised in the internet.

ELEPHANT CONSERVATION

Several threats like habitat loss, degradation and fragmentation -leading to the elephant isolation in habitat patches forming the so called `pocketed herds´, have caused the elephant population size decrease during the last decades. As keystone species, they have a large effect on its environment relative to its abundance. It is a species which plays an important role in maintaining and balancing the structure of an ecological community and affecting many other organisms within this community. The loss of elephants from one particular site would mean that all the biological interactions and ecosystem processes in which they are involved, would also be lost.

As “umbrella species”, the African elephants are selected for making conservation-related decisions, because by protecting them, another co-existing species benefiting from them are also preserved.

Often species conservation can be quite controversial and subjective, and as a consequence very difficult. The identification of flagship species, keystone species and umbrella species makes conservation decisions easier, more plausible and convincing.


References: 
WWF
African Journal of Ecology
Think Elephants International
The Asian Elephant: Ecology and Management, R. Sukumar, Centre for Ecological Sciences, Indian Institute of Science, Bangalore, India 

Male Hippo Anatomy

In my previous blog post, I talked a bit about the rear ends of yellow-backed duikers.  Today I wanted to mention hippo rears -- fair warning that this will be about male parts, so if that's not your thing, maybe you'd like to look at some Chimp&See videos in classification instead.

Most male hoofed mammals have testes that are located in a scrotum outside the core of the body.  There are just a few exceptions: rhinos, tapirs, and hippos.  While we won't see rhinos or tapirs on Chimp&See, we have had quite a few pygmy hippo videos.  Not only do these guys lack external testes, but they also have a rather unusual pendulous penis that faces backwards.  Have a look at some pygmy hippos below, and next time you're on Chimp&See, try to spot more of these unique males!

Original videos at ACP00025kg, ACP0005pdy, ACP0005oii, ACP000f2zl

Sources:
Estes, R. Despard. "The behaviour guide to African mammals: including hoofed mammals, carnivores, primates." Johannesburg: Russell Friedman Books CC (1991).
Kleisner, Karel, Richard Ivell, and Jaroslav Flegr. "The evolutionary history of testicular externalization and the origin of the scrotum." Journal of biosciences 35.1 (2010): 27-37.

A new chimpanzee behavioural variant! Algae fishing in Bakoun, Guinea

We began the Pan African Programme: the Cultured Chimpanzee (PanAf) in the hopes of discovering new chimpanzee cultures and cultural variants in previously poorly- and unstudied populations. Earlier this year we documented the occurrence of a new behaviour, chimpanzee accumulative stone throwing, present in four populations in West Africa. Today we are happy to announce the publication of our new study reporting on an new behavioural variant of algae fishing by chimpanzees in Guinea!

We describe the first camera trap footage of algae fishing behaviour at a PanAf temporary research site in Bakoun, Guinea where the tool-use appears quite different from what is known from a nearby long-term chimpanzee site at Bossou, Guinea and also differs from previous reports of rare algae scooping in Congo. 

All age and sex classes of Bakoun chimpanzees were observed to successfully fish for algae in a river, stream or pond using woody branches or twigs as fishing rods. The tools were on average longer and sturdier than the algae fishing tools described at Bossou. 

The freshwater green algae being targeted was of the same genus, Spirogyra, that is fished at Bossou, but grows on the bottom of the river and stream beds and does not collect on the surface as it does at Bossou. As such, the ecology of the particular algae growing at each site may drive the types of tools necessary to harvest the algae. We suggest that the algae likely provides a substantial nutritional benefit to the chimpanzees at Bakoun, especially during the dry season when chimpanzees were observed to fish for up to an hour at the same spot. 

These videos have not yet been up on Chimp&See yet and you can see that one of the limitations of our study was that the chimps from these videos have not yet been identified. We're hoping to have these up sometime in 2017 and look forward to matching some chimps with you then!

Citation:
Boesch C, Kalan AK, Agbor A, Arandjelovic M, Dieguez P, Lapeyre V, Kühl HS (2016) Chimpanzees routinely fish for algae with tools during the dry season in Bakoun, Guinea. American Journal of Primatology doi 10.1002/ajp.22613