Resurrecting an Amazon forest inventory of the Brazil nut family (Lecythidaceae)

Summary: The Brazil nut family – Lecythidaceae – is one of the most important families of trees in the Amazon basin. Yet compared to tree families of temperate forests, the group is extremely understudied. In collaboration with Brazilian colleagues, our lab has selected neotropical Lecythidaceae as a model clade for integrated studies of systematics, ecology and evolution in Amazon trees. This post summarizes a few interesting features of the group, and describes plans to revive a Lecythidaceae research project near Manaus, Brazil.

“Tio Romeu” Cardoso surveys trees in one of the BDFFP forest reserves, circa 1994. Tio Romeu was a skilled woodsman who helped to establish the Km 41 Lecythidaceae plot. A canopy tree species discovered in the plot — Eschweilera romeu-cardosoi S.A. Mori — bears his name. Photo credit C. Dick

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A critical take on “Persistent effects of pre-Columbian plant domestication on Amazonian forest composition”

Summary: Levis et al. (SCIENCE03 MAR 2017 : 925-931) challenge the idea that Amazon forests were largely untouched by humans prior to 1492. Specifically, they show that forest plots near archeological sites are enriched with useful tree species relative to plots located farther away from these sites. This is an intriguing finding, but the idea that prehistoric gardening has broadly shaped Amazon forests is problematic: (1) Amazon forest inventory plots are spatially biased toward human settlements (both ancient and modern) so broader extrapolation is not warranted; (2) Most useful tree species have short lifetimes and their local enrichment should not persist after several hundred years; (3) Amazon people still care for these useful tree species, making it it difficult (if not impossible) to disentangle ancient and modern impacts. The simplest interpretation is that Amazon research plots are often established in forests used by rubber tappers, small-scale farmers, or other recent peoples.

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Staten Island’s buck sterilization plan: what could possibly go wrong?

Summary: Staten Island is confronting urban deer overabundance with a plan to sterilize all of its male deer. Animal rights groups praise the plan as forward looking and humane, but it is neither. It will be difficult to implement, wildly expensive, and it will alter the reproductive behavior of male and female deer, leading to an increase in vehicular collisions and physiological stress. A deer cull — possible even in Staten Island — would give the remaining deer a more natural life and improve deer-human interactions.

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Narrow channels isolate Staten Island (red) from New Jersey (orange) and New York City (yellow). https://commons.wikimedia.org/w/index.php?curid=10668334

In Ann Arbor deer management has been a hot news item for nearly a year. When it comes to non-lethal methods, someone occasionally  brings up the possibility of buck sterilization (i.e. vasectomy). The idea is rejected fairly quickly. Unlike the more sedentary female deer (does) bucks travel broadly and they are polygamous; i.e. they will mate as often and with as many females as they can. If you manage to sterilize one buck, another will come to take its place.Read More

The pseudoscience of non-lethal deer management

Summary: Following a controversial deer cull, the city of Ann Arbor is considering non-lethal methods to deal with its burgeoning deer population. The Humane Society of America (HSUS) has aggressively promoted these methods in Ann Arbor and elsewhere but their scientific rationale is misleading at best. This post discusses biological misinformation at the heart of the HSUS deer campaign.

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Whitetail deer photographed from an Ann Arbor home on January 20, 2016. The large numbers of yearlings suggest that the herd is undergoing an exponential growth phase.

Ann Arbor recently approved a deer cull in which marksmen shot 63 deer; the venison was distributed to the needy. Although the cull was planned with public input and an emphasis on safety, opposition groups protested relentlessly and filed lawsuits (some still pending) to halt the cull. A full listing of MLIVE articles on the topic can be found here. The timeline and local political context can be found here and here.
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Welcoming Tamara Milton to the lab

We are delighted to welcome Tamara Milton as a new PhD student in the lab starting this fall. Tamara graduated from Bucknell University with a dual degree in Biology and Environmental Studies and a minor in Spanish (Magna Cum Laude). Following her 2012 graduation, Tamara spent two years as a Peace Corps volunteer in Paraguay promoting environmental conservation. This past summer, Tamara did ecological studies in Sleeping Dunes, Michigan focused on climate change impacts on federally threatened Pitcher’s thistle. Tamara is interested in doing  conservation-oriented ecological research in Latin America.

On Ticks, Taxonomy and Lyme Disease

Summary: The tick Ixodes scapularis transmits Lyme Disease and is expanding its range across the eastern U.S. As we discovered recently, basic tick ID skills relevant to disease treatment appear to be lacking in the medical community.

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Engorged tick (Ixodes sp) acquired by U-M Botanist near Chelsea, MI in late March 

Last week Herbarium associate Mike P. sent a staff email to warn us of deer ticks. After doing some outdoor work west of Ann Arbor he found an engorged tick on his chest (genus Ixodes) that left a small rash. The tick (see above photo) looked like an adult of the blacklegged tick Ixodes scapularis, which transmits the bacteria that causes Lyme Disease.

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Oak-hickory forest: a vestige of Native American land use?

Summary: Oak-dominated forests in the E.S. George Reserve and elsewhere in the eastern U.S. are being replaced by maples and other fire-sensitive trees. Oak forests may be a legacy of Native American fire practices that predate European settlement.

ESGR forest profile

Oak trees in the Big Woods Plot of the E. S. George Reserve

Two years ago a U-M team* established a Forest-GEO tree inventory plot in the E.S. George Reserve (see 2014 blog post; or listen to this NPR interview). Students and faculty mapped and measured all woody stems ≥1 cm diameter in 23 hectares of oak-hickory forest (the plot is the size of 46 football fields!). “Big Woods” plot includes > 45,000 stems from 41 tree and shrub species.

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Welcoming NSF post-doc Greg Stull

We will be welcoming a new post-doc in the lab next term – Greg Stull. Greg, who is finishing his dissertation in the Soltis lab, was awarded an NSF post-doctoral fellowship for “Research Using Biological Collections”. These fellowships are meant to support transformative science that employs biological collections.

The title of Greg’s post-doctoral fellowship is ” Integrating diverse collections data for deep-time distribution modeling in a tropical flowering plant family (Icacinaceae) with an extensive fossil record.”  Stephen Smith and I (Chris Dick) will serve as the sponsoring scientists.

Below is part of the abstract for Greg NSF Fellowship.

Understanding how species have responded to previous instances of climate change is critical for predicting the impact of future climate change on the distribution of biological diversity. Because the fossil record is highly incomplete, additional tools are necessary to reconstruct historical distributions at different points in the past (e.g., when the earth’s climate was considerably warmer during the early Eocene, ca. 50 Ma). Species distribution modeling (SDM) has emerged as a powerful computational tool for modeling the ecological requirements of species, using the wealth of locality/geographic data available for modern species in natural history collections. SDM has been used extensively to predict possible future distributions as shaped by climate change; the application of SDM for reconstructing distributions in deep time, however, has been underexplored, despite its potential for understanding how climate change has shaped the diversity and distribution of organisms through time. The fellowship research will explore and expand methods of using geographic data from modern species, obtained through online repositories of collections data from around the world (e.g., GBIF, iDigBio), to generate species distribution models of extinct species, allowing for the reconstruction of distribution patterns across broad time scales (e.g., the past 65 Ma). This research will use as a model the pantropical plant family Icacinaceae, which has an extensive fossil record, allowing for the validation of the historical projections and, by extension, the methods used to generate them. In particular, this research will investigate the climatic suitability of major land bridges/rafts for the migration of tropical plants throughout the Cenozoic (65 Ma to present). The will constitute one of the first studies to employ SDM across such a broad time scale, using the fossil record to validate the results. This research will therefore serve as an important proof of concept for this approach, and the novel methodological tools generated will advance future research related to biogeography and climate change.

Welcome Greg!