Alle berichten door rhjerkens

UvA-TREUB Symposium Advances in Tropical Research

Here you can find information on the yearly symposium organised by the Treub foundation together with the University of Amsterdam.

Date: 18th of  October 2019

Time: 14:00-17:00 (starting time was changed on 08-10-2019!)

Location: Science Park, Building G, Room G2.10


14:00-14:10 WELCOME & OPENING

14:10-14:30: Characterization of phytoliths in mid-elevation Andean forests

Seringe Huisman (University of Amsterdam/Treub grant awardee)

14:30 14:50: Extinction-driven changes in frugivore communities on tropical islands: worldwide and in Mauritius

Julia Heinen (University of Copenhagen, Denmark)

14:50 – 15:10: Are the current Amazonian fires unprecedented?

Crystal N.H. McMichael (University of Amsterdam)

15:10 – 15:30: On the relationship between tiger conservation and water management

Jasper Griffioen, Hanne Berghuis & Ewa van Kooten (Utrecht University)

15:30-16:00: TEA

16:00 – 16:45: Assembling the diverse rain forest flora of SE Asia by evaluating the fossil and molecular record in relation to plate tectonics

Robert J. Morley1,2 (1Palynova, 2Southeast Asia Research Group, Royal Holloway University of London, UK)

17:00: DRINKS– Science Park 904, IBED Common Room, C4.222


Seringe Huisman (University of Amsterdam/Treub grant awardee)

Biosketch – Seringe is currently finishing her Master’s in Biology at the University of Amsterdam. During her Bachelor’s program, she became interested in Tropical Ecology and did an internship with Dr. Crystal McMichael in Tropical Paleoecology. She analyzed fossil charcoal and phytoliths from Ecuadorian lake sediments, reconstructing Holocene vegetation history from the western Amazonian lowlands. 

She continued her research in Paleoecology during her Master’s project, this time in a mid-elevation Andean setting. Thanks to grants provided by the Treub Maatschappij and the Amsterdam University Fund, she got the chance to perform fieldwork on the eastern Andean flank in Ecuador. Her project led to the characterization of new mid-elevational palm phytoliths, which were previously unstudied and enable comprehensive local vegetation reconstruction.

Abstract – Characterization of phytoliths in mid-elevation Andean forests

Mid-elevation Andean forests are some of Earth’s most diverse ecosystems, yet their ecological history remains understudied. We provided the first reconstruction of mid-elevation Andean vegetation (400 years) using phytoliths, which are silica bodies produced by many Neotropical plants that preserve in fossil records. Unlike pollen, that is wind-dispersed, they represent local-scale vegetation dynamics. The Andean phytolith assemblages showed the potential to indicate changes in the cloud base position through time, which strongly influences the distribution of many plant and animal species.

Julia Heinen (University of Copenhagen, Denmark)

Biosketch Julia Heinen has completed her BSc and MSc at the University of Amsterdam. During this time she became interested in extinctions of fruit-eating animals on islands and published her first paper and large database on this topic. She is now halfway through her PhD in Island Macroecology at the University of Copenhagen at the Center for Macroecology, Evolution and Climate. For this, she is still working as an island macroecologist on the effects of extinction of fruit-eating animals on plants. Besides the global scale island comparisons, she is investigating the frugivore community at local scale in Mauritius and the Krakatau Islands. Julia is also Student-at-Large at the International Biogeography Society, representing young biogeographers. She enjoys explaining her research with videos (

Abstract – Extinction-driven changes in frugivore communities on tropical islands: worldwide and in Mauritius

Island communities are most vulnerable to extinctions and this affects the interactions between species. We have particularly lost a lot of large, fruit-eating animals. These large frugivores are the ones capable of dispersing the largest seeds, and their loss will in turn affect the plants that are dependent on them. Small and isolated islands have lost the highest proportion of their frugivore community, with many islands losing almost all native seed dispersers. Julia Heinen will discuss extinction-driven changes in frugivore communities on islands worldwide and at a local scale, on Mauritius, famous for the extinction of the Dodo. 

Crystal N.H. McMichael (University of Amsterdam)

Biosketch – Crystal McMichael is Assistant Professor at the Department of Ecosystem and Landscape Dynamics (University of Amsterdam). She is a paleoecologist, tropical ecologist, and biogeographer. Her research focuses on past fire and vegetation change across tropical ecosystems, and the role of humans and climate change in structuring those dynamics. She is also the Vice President of Conferences for the International Biogeography Society.

Abstract – Are the current Amazonian fires unprecedented?

The recent fires across Amazonia have attracted large amounts of academic and public attention. In this talk, I will explore the spatial and temporal patterns of fires in Amazonia. I will put the present fire regimes in the context of those seen in the past, and discuss implications for the future. This talk will highlight ongoing work that we hope to submit for publication soon.

Jasper Griffioen (Utrecht University)

Biosketch: JasperGriffioen is professor of Water Quality Management at Utrecht University (2011 to date) and expert researcher at TNO Geological Survey of the Netherlands (1991 to date). He is specialised in environmental hydrology and geochemistry within the framework of sustainable management of soil and water resources. He performed studies for a wide variety of geographical settings and a broad range of environmental management issues, ranging from an acid crater lake in Indonesia to disposal of radioactive waste in the deep subsurface of the Netherlands. Many of his projects refer to the risks and impact of anthropogenic measures on groundwater and subsequent effects on drinking water and groundwater-dependent ecosystems. At TNO Geological Survey, he pays attention to the geochemical and hydrological characterization of the subsurface, which has given him extensive insights in geo-scientific surveying of our environment as well as its importance. Preferably, he combines field campaigns with modelling studies.

As member of the former ministerial Dutch Technical Committee on Soil, he was involved in c. 100 ministerial advices during October 2007 – March 2016. He has been an expert in several cases for Dutch Courts of Justice as well as for the Netherlands Commission of Environmental Assessment. His research frequently reaches Dutch national newspapers and other media.

Abstract – On the relationship between tiger conservation and water management

There are less than 4000 wild tigers alive. The Global Tiger Initiative aims to double the number of wild tigers in 2022 relative to 2010. The Terai at the foot of the Himalayas is the most important conservation area of tigers. Clearly, habitat conditions are of key importance to double the tiger population. Typically, the tiger habitat consists of free roaming deer, which rely on open grasslands for grazing. The grasslands areas are deteriorating (e.g. overgrown by forest) which threatens the deer and consequently tiger habitats. The hydrology and river morphodynamics are two abiotic factors that seem to control the grassland dynamics in the Terai. Associatedly, the impact of water management measures needs attention, where the following question may become raised: what is the impact of gravel extraction in the river floodplain, what is the impact of intake of river water for irrigation. Two studies will be briefly presented that address these two factors: one of them focuses on the hydrology of the Karnali River in Western Nepal. This river is the western boundary of Bardia National Park, where c. 80 tigers exist. The other addresses the groundwater hydrology at Bardia NP, including the interaction with the Karnali River.

Robert J. Morley

Biosketch: Robert (Bob) Morley was introduced to palynology by the late John Flenley, and was John’s first research student, and was further inspired by Jan Muller from the Rijksherbarium in Leiden. After completing a PhD thesis on the Late Quaternary palynology of Sumatra and Malaysia he joined Robertson Research International, a geological consultancy company as ‘Tertiary palynologist’ mainly working in SE Asia and West Africa. In 1986 he was acting manager for a short while at the Robertson Bogota office, where he met Henry Hooghiemstra and Carina Hoorn for the first time in a remote field on the Sabana de Bogota!

In the early 1990’s he joined the British Geological Survey overseas division, and set up a palynology lab for the Indonesian Government in Jakarta, after which time he established the consultancy company Palynova, together with his wife Santi, which provides expertise in biostratigraphy to petroleum exploration companies and government research laboratories.

His major research interests are: evolution of tropical rain forests, resolving stratigraphic problems using biostratigraphy, and especially using the methods of ‘sequence biostratigraphy’ to develop a better understanding of sequence stratigraphy. A further primary aim is to ensure that unpublished petroleum industry archives of biogeographic interest are brought into the public domain. He authored a book ‘Origin and Evolution of Tropical Rain Forests’ published by Wiley, and has published over 120 papers on biostratigraphy and SE Asian geology.’

Abstract Assembling the diverse rain forest flora of SE Asia by evaluating the fossil and molecular record in relation to plate tectonics

In the 1960’s, the renowned Russian botanist Armen Takhtajan published a treatise suggesting that Southeast Asia formed the birthplace of the angiosperms. This idea prevailed for 40 years, but today, the opposite seems more likely, that Southeast Asian rain forests are the youngest of the three major rain forest blocks. The ultra-diverse flora of the Southeast Asia has become established largely as a result of immigration following different phases of plate tectonic collision during the Cenozoic. However, trying to piece together the details of the tectonic events that led to the different plate tectonic and palaeoclimatic scenarios that facilitated the different phases of floristic immigration into the region leaves many unanswered questions. There are major issues regarding the timing of plate collisions, the positions of plates and microplates through time, the areas of origin of the main clades and the timing of floral and faunal dispersals. This discussion builds on the palaeoclimatic maps and dispersal events proposed recently by Morley (2018) firstly by examining Late Cretaceous to Paleocene dispersals from Africa to the Indian Plate, and secondly by an evaluation of dispersals from India to SE Asia during and after the Palaeogene collision of India with Asia. Thirdly, the history of upland Sundaland floras over time is evaluated, from the pollen record of gymnosperms and temperate angiosperms from unpublished petroleum exploration wells, contesting the timing and direction of the rotation of Borneo into its present position during the mid-Cenozoic. To move forward, on the one hand detailed palynological and palaeobotanical evaluations are needed from the African Late Cretaceous, and the Palaeogene of both northern India and the Southeast Asian region (the most recent studies of Palaeogene leaf floras from Sumatra and Borneo was by Geyler and Heer in the 1870’s). This needs to be coupled with novel evaluations of plate tectonics prior to the Indian collision with Asia, and for the Sunda region utilising new dating that is emerging for the multiple non-marine basins that formed across the region during the Paleogene.  

Reference Morley, R.J. (2018). Assembly and division of the South and South-East Asian flora in relation to tectonics and climate change Journal of Tropical Ecology34:209–234.

Symbiotic coral-dwelling crabs on Bonaire’s reefs

Dr. S.E.T. van der Meij and S. Bähr (GELIFES, University of Groningen , Groningen, The Netherlands)

Bonaire, Dutch Caribbean – 26 July – 17 August 2019

Coral reefs encompass the highest biodiversity of any marine ecosystem. Stony corals provide a large number of habitats that are home to various invertebrate species, many of which live in a close symbiotic relationship with a specific host coral. In an environment that is teeming with symbiotic relationships the minute and easily overlooked coral-dwelling gall crabs of the family Cryptochiridae represent a prime example of obligate symbiosis. These crabs are named after their close relationship with their coral hosts; they cause the development of a gall by modifying their hosts’ tissue.

The reefs along Bonaire’s coast are amongst the healthiest reefs in the Caribbean, however they are relatively understudied compared to nearby Curaçao and other islands with a strong research infrastructure. In this study we aimed to collect occurrence data of three Atlantic gall crab species (Fig. 1) over depth intervals along the Bonaire coast, to better understand the distribution of symbiotic species on coral reefs. In combination with coral cover measurements the results of this study provided us with baseline data about the status of Bonaire’s reef. Moreover, using the same approach as a similar study carried out on the reefs off Curaçao in 2015, it allows us to compare the results between the two islands.

We studied 25 dive sites along the west coast of Bonaire and around Klein Bonaire using 5-m2 belt transects (10m x 0.5m) at three different depths (8m, 12m, 18m), resulting in a surveyed area of 375 m2. Within each transect we measured the diameter of all corals known to host gall crabs, and counted the number of dwellings on each individual colony.

Our observations of the crabs Troglocarcinus corallicola and Kroppcarcinus siderastreicola represent new species records for Bonaire. Direct comparisons of coral cover data and gall crab density between Curaçao and Bonaire provides interesting insights in the status of the two reef systems. On Bonaire 19 out of 22 known host corals were observed in the transects, compared to 15 out of 22 of Curaçao. Strikingly, the number of examined coral colonies on Bonaire was with 4023 more than twice as high as the number of colonies examined on Curaçao (1874 colonies). The crab density of Opecarcinus hypostegus was with 6,3 crabs per m2, however, exactly the same at both localities. Troglocarcinus corallicola had with 5,22 crabs/m2 a slightly higher density on Bonaire than on the reefs off Curaçao (4,02 crabs/m2). Unfortunately the dwelling data for K. siderastreicola had to be excluded from the analyses due to some misidentifications of their dwellings in part of the study. 

Our results suggest that Bonaire’s reef system has a significantly higher coral cover than the reefs on Curaçao. Using further statistical analyses we will check for significant species level differences between the two islands, as well as between the various dive sites off Bonaire. Certain sites are heavily impacted by divers or industry (e.g. cruise ships, salines), whereas others are further away from human activities or rarely visited by divers – and we are keen to see if this impacts the distribution of the symbiotic gall crabs.

Figure 1: Dwellings with gall crabs found on corals off Bonaire. (A) Opercarcinus hypostegus in Agaricia lamarcki, (B) Kroppcarcinus siderastreicola in Siderastrea siderea, (C) Troglocarcinus corallicola in Orbicella annularis. Pictures: Pieter de Groot.

Palliative care needs and preferences in Ethiopia

Dr. J.J. Beltman and drs. M. de Fouw (Leids Universitair Medisch Centrum, Leiden, The Netherlands)

In Sub-Saharan Africa where life expectancy is short, supportive and palliative care for severely ill patients are hardly available. Ethiopia is one of the countries where lack of access to pain relief and palliative care are apparent. In our study we assessed palliative care and support programs for women, mostly affected by cervical cancer and breast cancer. Breast and cervical cancer are the leading cancers among women in Ethiopia, with 15244 and 6294 new cases each year.

Most women identified with cervical and breast cancer present in advanced stage where curative treatment is no longer an option. Comprehensive palliative care services are needed but scarce, strong analgesics like morphine are hardly available and knowledge of palliative services in health facilities is limited.

We aimed to understand the current practices of palliative care, and the needs and preferences of both patients and their caregivers. We conducted in-depth interviews with terminally ill women (34) and their caregivers (27), and key informant interviews (16) with community leaders, religious leaders, health care professionals and policy makers.

All patients received support from the palliative care programs, but stated that it was insufficient to meet their needs. Most women (4 out of 5) suffered from moderate to severe pain, half of the women frequently experienced moderate to severe difficulties with sleeping or eating.

“She (the volunteer provider) has been caring. However, I am not happy and lose hope when my pain comes back. I then feel uncertain about my life. I feel like am dying. It is bad to live under uncertainty, losing my ability to make decisions about myself. The volunteer at times fails to help under such circumstances” (42 years old female patient)

Besides pain, and difficulties with sleeping or eating women suffered from other complaints like cough and vaginal bleeding, that strongly limited their daily activities.

I bleed every time. It clots and clots and brought offensive smell since I do not have support to clean it and of course no one comes closer. I got weaker and weaker. Only recently volunteers came to help me – thank God.” (38 year old  female patient)

Women felt very worried about their situation, and did not often talk about their worries and concerns with their caregivers. Religion did support women in feeling more hopeful about their situation.

Caregivers were often related to the patients, in half of the cases a daughter or son cared for their own mother. Neighbours and other community members supported less than 1 in 4 patients. Most caregivers experienced sad feelings while providing support to terminally ill women and experienced the work as consuming. At the same time, they felt confident about the care they were providing although they missed information on the diagnosis, signs and symptoms.

Health care professionals, community leaders, religious leaders and policy makers recognized the existing gap in palliative care provision and lack of knowledge on palliative care services. They pointed out the lack of organization of care, lack of skilled providers, lack of budget and low priority that is given to palliative care services.

During our study we found that only a selected group of women was included in the support programs, although the programs define palliative care in a broad definition including chronic illnesses like diabetes and hypertension. Considering the population size in the areas where the programs are active, many women with palliative care needs are not identified.

Our study demonstrates that there is an unmet need for palliative care services, that palliative care services should focus more on pain and symptom relief including training of related caregivers, and palliative care services should be integrated with existing community networks, religious structures and local and national health systems.

One of the women receiving palliative care in her own home, Sidama zone, Ethiopia

Wild food plants used by Baka people in southeast Cameroon

Prof. Dr. Tinde van Andel (Naturalis Biodiversity Center)

The Baka (Pygmies) are former hunter-gatherers, living in the tropical rainforest near Lomie, southeastern Cameroon. The goal of the van Andel et al. expedition (1 April-25 April 2019) was to collect botanical vouchers for the edible forest plants that were reported earlier during interviews by postdoc Dr. Sandrine Gallois on wild food collection and dietary preferences among Baka in the village of Le Bosquet. The fieldwork has been completed: we collected 104 botanical vouchers of wild edible plants from secondary and primary forest. We matched all Baka names mentioned during the previously conducted interviews, with the exception of four species. These are collected at the moment by Gallois herself, after she received field training in the collection, documentation and preservation of ethnobotanical specimens by the applicant.

Van Andel and Heger discuss with Baka field guides in the forest. Picture: S. Gallois.

We (van Andel, student Heger and Gallois) also collected several edible species that were not in the preliminary database. A total of 11 different wild yams were collected, and eight different Irvingia species. Our results show that the Baka make ingenious use of the Central African rainforest, characterized by large-fruited trees adapted to dispersal by large, ground-dwelling mammals (elephant, chimpanzees, gorilla’s, etc.). Many of these large fruit species, some with unpalatable flesh, are cut open to obtain the seed kernels, which can only be consumed by humans after long and complicated detoxification techniques, such as roasting, soaking in running water, smoke-drying, etc. These seed kernels are rich in proteins and fats, and form an important component in the Baka diet.

Student Heger interviewing Baka informant, van Andel pressing specimens in the background. Picture: S. Gallois.

We made sure to include field assistants of different age, gender and specializations (e.g., healers, hunters, grandmothers), which allowed us to document several types of ritual food: specific plant species only eaten by elephant hunters, post-menopausal women or small boys after their circumcision ceremony. Most of the wild food species are collected in primary forest, and we documented several edible species that have not been previously documented as eaten by humans in the literature (e.g., roots of Palisota barteri, stems of Anchomanes difformis and seven species of edible ferns). As all Baka are now somehow involved in agriculture, we could not make a distinction in wild plants use between farmers and true hunter-gatherers. However, the botanical variety of wild-gathered food plants remains very high, even though people now also spend time in cultivating cassava and bananas. Unfortunately, illegal logging of Baillonella toxisperma (Sapotaceae) and Diospyros (Ebenaceae) in the area deprives the Baka of some of their most valuable sources of edible fruits and oil. The Baka villagers requested our help in writing a book on their wild food plants, to which we agreed.

Fresh kernels of Klainedoxa gabonensis (Irvingiaceae) , one of the most frequently consumed wild seed species around Lomie. Picture: S. Gallois.