In our new paper, The contribution of community-based conservation models to conserving large herbivore populations published in the journal Scientific Reports, we demonstrated using long-term distance sampling that community-based conservation areas in the Tarangire Ecosystem have contributed to the stabilization of the population of migratory wildebeests and zebras as well as elephants and giraffes.

On Saturday 21 September, more than 1,400 students and teachers from three secondary schools in the Tarangire region of Tanzania celebrated wildlife and conservation in a ‘Giraffe Bonanza’ event sponsored by Wild Nature Institute. Wearing specially made t-shirts that read “Okoa Twiga” (“Save Giraffes”), students led tours of Wild Nature Institute’s tree nursery, which has distributed more than 17,000 tree seedlings for free to the local community!

After the nursery tour, students staffed information booths about water filtration, birds, snakes, giraffes, elephants, zebras and Wild Nature Institute’s Celebrating Africa’s Giants storybooks (Juma the Giraffe, Our Elephant Neighbours, and Helping Brother Rhinoceros).

After the tours and demonstrations came more fun – the big bonanza! The students were entertained by professional and student dancers, two professional comedians, professional singer Shubert (who created the song and video Okoa Twiga that Wild Nature Institute produced several years ago, click here to watch), and their fellow students participating in creative games and receiving prizes. The entertainment also included useful lessons such as how to escape a charging buffalo. Throughout it all, the students echoed the refrain of Okoa Twiga, cheerfully answering “Twiga” when the emcees called out “Okoa”!

Once again, Wild Nature Institute's education power team of Veila Makundi and Glory Mbuya have delivered extraordinary and memorable conservation-focused activities. Their deep, ongoing, long-term relationships with these schools ensure that our programs are successful.

Of course, none of this would be possible without the financial support of our partners and donors. Thank you so very much for making Wild Nature Institute’s community conservation and education programs possible. The children in Tanzania are benefiting greatly.

Yesterday (31 July) was World Ranger Day! Wild Nature Institute celebrates and supports wildlife law enforcement rangers who dedicate their time and energy to safeguarding giraffes and other wildlife from poaching. Yesterday, our education program staff, Veila, James, and Glory, took 35 Tanzanian children and 3 teachers from St. Jude's Primary School in Mtowambu to Tarangire National Park to meet the rangers and say 'thank you' to them. The visit was a surprise for the rangers (although planned ahead with the Chief Park Warden).

The kids carried a big sign that said "Happy Rangers' Day. Thank you so much rangers for guarding wild animals and making our national parks attractive to the world." The kids all wore special t-shirts we made that said "Happy Ranger's Day" with a picture of giraffes. They delivered hand-written thank-you notes attached to a big giraffe poster. They met many park rangers, including the head of rangers at the Tarangire National Park headquarters. Lots of park visitors from countries around the world were interested and took photos. This helped raise global awareness about the important role that park rangers play in maintaining biodiversity.

The verdict: the rangers were very surprised and really happy!

Afterwards, the kids went for a fun safari to enjoy the wild animals that the rangers help to keep safe.

Of course, all of this is made possible thanks to the financial support and partnership of our donors. Many many thanks for being a part of Wild Nature Institute's "Team Twiga" (team giraffe) and helping with giraffe conservation and education in Tanzania!

World Giraffe Week 2024 in Tanzania was a resounding success, thanks to our fantastic education coordinator Veila Makundi and our entire Wild Nature Institute team. We welcomed our newest member of the education team, Glory Mbuya, and James Madeli helped out and took lots of great photos and videos of the activities.

The kick-off to World Giraffe Week was interviews by Wild Nature Institute's Veila Makundi  on 2 Arusha-based radio stations reaching thousands of Tanzanias about giraffes and what everyone can do to protect them. Then it was off to the schools for activities! More than 540 kids and teachers from 5 schools participated, with a highlight being a 'ngongoti', a man on stilts dressed like a giraffe, which delighted the children. The children made giraffe posters with unique spots (to be delivered to park rangers on World Ranger Day, 31 July), danced and sang, and had a great time celebrating Tanzania's national animal and learning how they can help save them.

Of course, absolutely none of this would have been possible without the amazing support from our donors around the world. Thank you so very much, from all of us at Wild Nature Institute.

This year's theme is GIRAFFE SPOTS! Visit www.worldgiraffeweek.org to learn more about their spots and to try some fun activities to celebrate our tall friends!

Food, then sex, drove the evolution of the giraffe's long neck, according to a new study by Penn State and Wild Nature Institute published in the journal Mammalian Biology.

Although male and female giraffes have the same body proportions at birth, they are significantly different as they reach sexual maturity. Females have proportionally longer necks and longer bodies than males, which might help with foraging and child rearing, while males have wider necks and longer front legs, which might help win fights against other males and with mating. Credit: Penn StateWhy do giraffes have such long necks? A study led by Penn State biologists explores how this trait might have evolved and lends new insight into this iconic question. The reigning hypothesis is that competition among males influenced neck length, but the research team found that female giraffes have proportionally longer necks than males—suggesting that high nutritional needs of females may have driven the evolution of this trait.
The study, which explored body proportions of both wild and captive giraffes, is described in a paper that appeared today, June 3, in the journal Mammalian Biology. The findings, the team said, indicate that neck length may be the result of females foraging deeply into trees for otherwise difficult-to-reach leaves.
In their classic theories of evolution, both Jean Baptiste Lamarck and Charles Darwin suggested that giraffes' long necks evolved to help them reach leaves high up in a tree, avoiding competition with other herbivores.
However, a more recent hypothesis called "necks-for-sex" suggests that the evolution of long necks was driven by competition among males, who swing their necks into each other to assert dominance, called neck sparring. That is, males with longer necks might have been more successful in the competition, leading to reproducing and passing their genes to offspring.
"The necks-for-sex hypothesis predicted that males would have longer necks than females," said Doug Cavener, Dorothy Foehr Huck and J. Lloyd Huck Distinguished Chair in Evolutionary Genetics and professor of biology at Penn State and lead author of the study.
"And technically they do have longer necks, but everything about males is longer; they are 30% to 40% bigger than females. In this study, we analyzed photos of hundreds of wild and captive Masai giraffes to investigate the relative body proportions of each species and how they might change as giraffes grow and mature."
The researchers gathered thousands of photos of captive Masai giraffes from the publicly accessible photo repositories Flickr and SmugMug as well as photos of wild adult animals that they have taken over the past decade.
Because absolute measurements like overall height are difficult to determine from a photograph without a point of reference of known length, the researchers instead focused on measurements relative to one another, or body proportions—for example, the length of the neck relative to the entire height of the animal. They restricted their analysis to images that met strict criteria, such as only using images of giraffes perpendicular to the camera, so they could consistently take a variety of measurements.
"We can identify individual giraffes by their unique spot pattern," Cavener said. "Thanks to the Association of Zoos and Aquariums, we also have the full pedigree, or family tree, of all Masai giraffes in North America in zoos and wildlife parks, as well as their birthdates and transfer history.
"So, by carefully considering this information, when the photo was taken and the approximate age of the animal, we could identify the specific individual in nearly every photo of a captive giraffe. This information was critical to understanding when male and female giraffes start to exhibit size differences and whether they grow differently."
Giraffe body proportion measurement landmarks and definitions. Measurements are performed on images that are perpendicular to the plane of the body trunk and neck. Measurements were performed between landmarks lying along the two-dimensional perimeter of the giraffe. Credit: Mammalian Biology (2024). DOI: 10.1007/s42991-024-00424-4At birth, male and female giraffes have the same body proportions. The researchers found that, although males generally grow faster in the first year, body proportions are not significantly different until they start to research sexual maturity around three years of age. Because body proportions change early in life, the team limited their study of wild animals—whose ages are largely unknown—to fully grown adults.
In adult giraffes, the researchers found that females have proportionally longer necks and trunks—or the main section of their body, which does not include legs or the neck and head. Adult males, on the other hand, have longer forelegs and wider necks. This pattern was the same in both captive and wild giraffes.
"Rather than stretching out to eat leaves on the tallest branches, you often see giraffes—especially females—reaching deep into the trees," Cavener said. "Giraffes are picky eaters—they eat the leaves of only a few tree species, and longer necks allow them to reach deeper into the trees to get the leaves no one else can. Once females reach four or five years of age, they are almost always pregnant and lactating, so we think the increased nutritional demands of females drove the evolution of giraffes' long necks."
The researchers noted that sexual selection—either competition among males or preference among females for larger mates—was likely responsible for the overall size difference between males and females, as is the case in many other large, hoofed mammals that are polygynous—where one male mates with many females.
They suggest that, following the evolution of the long neck, sexual selection—including male body pushing and neck sparring behaviors—may have contributed to males' wider necks. Additionally, the longer forelegs of males may assist in mating, which the researchers said is a brief and challenging affair that is rarely observed.
"Interestingly, giraffes are one of few animals whose height we measure to the top of the head—like humans—rather than to their withers—the highest part of the back, like in horses and other livestock," Cavener said. "The female has a proportionally longer axial skeleton—a longer neck and trunk—and are more sloped in appearance, while the males are more vertical."
The research team is also using genetics to identify relationships in groups of wild giraffes to better understand which males are successful at breeding. The goal is to shed additional light on mate choice and sexual selection, as well as guide conservation efforts for this endangered species.
"If female foraging is driving this iconic trait as we suspect, it really highlights the importance of conserving their dwindling habitat," Cavener said. "Populations of Masai giraffes have declined rapidly in the last 30 years, in part due to habitat loss and poaching, and it is critical that we understand the key aspects of their ecology and genetics in order to devise the most efficacious conservation strategies to save these majestic animals."
In addition to Cavener, the research team at Penn State includes Monica Bond, academic affiliate of biology; Lan Wu-Cavener, academic affiliate of biology; George Lohay, a postdoctoral researcher at the time of the research who is now at the Grumeti Fund; Mia Cavener, a graduate student at the time of the research; Xiaoyi Hou, graduate student in the Molecular, Cellular, and Integrative Biosciences program; David Pearce, an undergraduate student at the time of the research; and Derek Lee, academic affiliate of biology.

Funding from Penn State, the Penn State Huck Institutes of the Life Sciences and the Wild Nature Institute supported this research.

Wild Nature Institute’s CAG education program organized a two-week Snake Blitz to teach Tanzanian children and teachers appreciation for snakes and prevent snake bites—which saves people and snakes alike. From 19 February to 3 March, a whopping 1,694 children from 5 primary schools in the Monduli district participated in the event, and learned all about the ecological importance of snakes, snake identification, how to behave around snakes to avoid conflict, and what to do if bitten. The kids learned through fun activities such as dramatic demonstrations and memory games, as well as with a beautiful snake activity book designed by our collaborators Mirthe Aarts and Megan Strauss together with Monica Bond, and produced by WNI. Children were given a questionnaire to fill out before and after participating, so we can quantify what the children learned and how our Saving People Saving Snakes education program affected their perceptions about snakes.

We warmly welcomed Gwido Aldo to our Saving People Saving Snakes program (see attached photos). Aldo is a Tanzanian snake expert and works with Tanzania Snake Conservation Education and Awareness (TASCEA) developing and delivering snake educational and awareness programs and collaborating with authorities to protect critical snake habitats. He is the perfect person to join our education team to share with children the importance of respecting these misunderstood and maligned reptiles. Veila and Jackline did an absolutely amazing job organizing the Snake Blitz with 2 visits to each of the 5 primary schools. They distributed 700 snake activity books, brought 175 children to visit the Meserani Snake Park to see snakes first-hand, and took 62 kids on a nature walk near the school. It was an exhausting but productive two weeks!

As always, we are deeply grateful to our donors for funding our CAG education program. While this activity was not directly about giraffes, our Saving People Saving Snakes project fosters respect and appreciation for all species in nature which bolsters community support for protecting all wildlife, including giraffes.

New research shows that for antelope populations in East Africa, it is not just about the weather but where they can roam. This highlights why we need big, connected spaces for conservation.
Environmental changes threaten naturally heterogeneous and dynamic ecosystems that are essential in creating and maintaining a rich, resilient, and adaptable biosphere. In East Africa’s savanna, antelope populations are vital for a healthy and functioning ecosystem. They shape the vegetation, disperse seeds, cycle nutrients, and provide food for other animals. A natural dynamic mosaic of vegetation types, water sources, and weather forms a delicate balance with the antelopes that is more and more disrupted by human influences and climatic changes. To protect these hotspots of biodiversity and enable the ecosystem to work properly, it is vital to maintain healthy antelope populations.
Previous studies have shown that densities of savanna antelopes vary based on location, season, and year, but no empirical studies had ever examined all these effects together. Simultaneously studying how environmental variation over space and time affects the local densities of antelope species could resolve whether location, or seasonal or annual variation is the most important factor driving local densities of these wildlife.
Using seven years of antelope monitoring data from the Tarangire Ecosystem in Tanzania, an international collaboration between the University of Zurich and the Wild Nature Institute examined this question. They found spatial factors explained the largest proportion of variation in density for four of the five antelope species they studied. These spatial covariates included proximity to water and human activities as well as vegetation community—suggestive of both bottom-up (resources) and top-down influences (avoiding natural predators) on local densities. The research was published in the journal Population Ecology. 
In the Tarangire Ecosystem, antelopes respond to changing climatic conditions and the fluctuating availability of resources by moving across space. Lead author Lukas Bierhoff, a graduate student in the Department of Evolutionary Biology and Environmental Studies at University of Zurich, said “these results demonstrate that antelopes depend upon water and forage availability, but are flexible in their responses to climatic variation when they have the option to move and seek out the necessary resources for the current conditions.”
Helping antelopes move across space to adapt to climate and habitat changes
As natural savanna habitats and climate are rapidly being altered by human activities, effective conservation strategies are needed to ensure the persistence of antelopes and all the services they provide to maintain healthy ecosystems. “This study provides further evidence that the protection of large, connected areas of different habitat types and permanent water sources are the best way to maintain high biodiversity and a functioning biosphere. Providing habitat options for the antelopes enables them to respond to a temporally changing world by moving across space,” Bierhoff said.
The research team also identified guilds of antelopes whose densities co-varied, and that might respond similarly to targeted and coordinated conservation strategies, thus increasing the efficiency of management actions.
“Effective conservation actions include protecting rivers and other water sources from diversion and pollution; reducing bushmeat poaching; keeping and restoring movement corridors; and maintaining the diversity of natural vegetation types” said Derek Lee, Wild Nature Institute principal scientist and senior author of the paper. “Antelopes are critically important to Tanzania’s economy as well as its ecology, so sustaining thriving populations of these animals is a win-win for people and wildlife.”

Citation: Bierhoff L, Bond, ML, Ozgul A, Lee DE. 2024. Anthropogenic and climatic drivers of population densities in an African savanna ungulate community. Population Ecology. https://doi.org/10.1002/1438-390X.12182

In 2023, the Wild Nature Institute continued our Science, Education, and Advocacy for wildlife in savannas of East Africa, a biologically rich region threatened by human activities.
We completed another year of the world’s largest study of giraffes using non-invasive photographic identification and DNA sampling. Together with our research partners around the world we published 4 new scientific papers about giraffes, and shared our results with other scientists, students, government decision-makers, and the media.
Our Celebrating Africa’s Giants education program reached ever more communities in Tanzania. Children learned about wildlife, ecology, and conservation in their classrooms; celebrated World Giraffe Week and Elephant Fun Day; nurtured and planted trees; and visited their local national parks for the first time.
Click here to learn about our accomplishments in 2023. We could not have met our goals without the support of our donors and partners. We are deeply grateful, as always.