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Photo by Sarah Oakman

Taking a Closer Look: Glass Collections at the Smithsonian

Glass is often thought of as a very stable, unchanging material. That, unless you drop it, it will be around forever. This, however, is far from the truth. Glass undergoes a unique and insidious type of degradation. It interacts with the humidity in the atmosphere, swapping out some of its own components for water, forming a brittle layer that most will recognize as the white scum that forms on glasses that have been run through the dishwasher a few too many times. This degradation, referred to as glass alteration, happens slowly, taking decades if not centuries to be noticeable. For most glass, glass alteration doesn’t really matter – the object is likely to be dropped or lost before anyone notices a change. But for glass objects in museums, some of which have been around for millennia, and all of which are intended to last a lot longer, the slow time scale of alteration can become a problem.

woman’s robes (munisak) - Arthur M. Sackler Gallery, Smithsonian Institution, Washington, DC: Gift of Guido Goldman, left: S2004.96; right: S2005.17.

The Power of Color: Using Synthetic Dyes as a Dating Tool for Museum Textiles

The desire to apply color to a surface is intrinsic to human nature and humans have searched for natural sources of color since prehistoric times. They found out that some minerals could be ground to obtain a fine powder, and this was the origin of the mineral pigments. But they also found out that some plants and animals (insects and mollusks) could yield color when mixed with hot water, and this was the origin of natural dyes. Pigments are suitable to be applied on surfaces by mixing them with a binding medium. Dyes can be applied to fibers in several ways in a water solution. This discovery led to one of the most spectacular forms of art and craftsmanship: dyed textiles.

56 million-year-old fossil pollen grains collected from Wyoming and photographed on the NMNH’s scanning electron microscope.

Tiny Fossils, Big Insight; How We Can Use Fossil Pollen to Understand Earth’s Climate History

As a palynologist, I study microscopic fossil spores and pollen that were produced by plants for reproduction. Pollen is highly important to the future of every plant and is made of an incredibly resilient substance (sporopollenin) ensuring that pollen can be preserved in rocks for hundreds of millions of years.

The author lowers a net into a topside ballast water tank to sample marine plankton and zooplankton

Port to Port: Ships Carry More than Just Our Cargo

Imagine this: you drive home from work, flip on the light switch, check your phone, and consider what to make for dinner. In the course of your routine, chances are you aren’t thinking about where your vehicle, light bulbs, electronics, appliances, or side of rice came from. In today’s world many raw commodities and finished goods are produced and traded globally. The items we depend on in our everyday lives, the materials we use to build our homes and roads, and the energy we consume to produce and operate them may originate from distant shores. Exports are often shipped, quite literally, on ships, creating a maritime network that reaches coastal ports around the world and supports our daily activities.

The author and his colleagues at their “office”.

Unraveling the “Hidden” Secrets Below One of the Most Biodiverse Regions on Earth

The spectacular biodiversity of the northern Pacific region of South America has drawn our attention since early botanical expeditions to the tropics conducted by European naturalists mostly during the 19th and 20th centuries. The Chocó region in northwestern Colombia, one of the rainiest places on Earth with a mean annual rainfall exceeding 10000 mm (1) is a remarkable example, which is home to an incredibly biodiverse tropical forest with ca. 3% and 6% of all known species of plants and vertebrates, respectively (2). However, a protracted history of social conflicts and sociopolitical isolation, dating back to the Spanish colonial period, has plagued the local afro and indigenous communities. As a result, our ability to carry out scientific research in this astounding region has been hindered, and in consequence, our knowledge on the evolution of this biodiversity hotspot and its hosting landscape is still limited.

The Yonahlossee salamander is a woodland species from the southern Appalachian Mountains in the United States (Brian Gratwicke)

Back from the Dead: Amphibians Continue the Fight Against Extinction

The silent killer fungus, Bd, was described by Smithsonian’s National Zoo veterinarians working with a scientist from the University of Maine (Longcore et al. 1999). This new fungus to science was found to cause the skin disease chytridiomycosis — which leads to a ‘heart-attack’ and death to frogs and salamanders. We now know that the killer fungus originated in Asia and that humans unintentionally spread it around the world causing dramatic declines and disappearances of many amphibians. The killer fungus threatens the survival of more than 500 species of amphibians across the globe. Bd is now known as one of the most destructive pathogens ever recorded in wild animals.

Omaca, the sample eating Tapir (tried, but did not succeed). Jokes aside, a remarkable animal to be around while doing science! Photo credit: Benjamin Blonder.

Help, a Tapir is Trying to Eat My Leaves! A Month of Plant Ecophysiology in Yasuní

It’s hard being a plant leaf - being eaten is a major risk. In tropical forests, ~10-15% (>70% in some species) of leaf area can be lost via herbivory (Cardenas et al., 2014; Coley & Barone, 1996). Plants may counteract herbivory via resistance, where chemical or mechanical defenses are used to deter herbivores, or resilience, where the effect of unavoidable damage is mitigated (Kursar & Coley, 1996).

the biodiversity of the Pantanal is outstanding. There is a great abundant of birds and a large quantity of mammals as shown in the big picture above. In this picture alone we can see at least four species of birds and a female Marsh deer. (W. Tomas)

Cattle Ranching and Sustainability in the Wetlands of Pantanal, Brazil

Sustainability is not a novel thing. Some studies have shown that most of the existing hunter-gatherers in the world (such as Pigmies in Congo, Agta Philippines and Ache in Paraguay) employ management strategies to protect the group from free-riders and guarantee sustainable use of resources. Thus, if we consider them as the closest societies to historical hunter-gatherer groups, sustainability has been part of our goal for as long as our species has occupied the planet. For over 300 thousand years, humans have been seeking strategies to develop in ways that “meets the needs of the present without compromising the ability of future generations to meet their own needs” 2. However, we may not all make it. Sustainability has changed from “the norm” to a rare and uncommon habit. Thus, how we can convince people to start to be conscious about something that seems to be an integral part of our own strategy to live as a group?

Dumas digging up a nest of Ectatomma ruidum. Photo credit: Jorge Alemán, Smithsonian Tropical Research Institute.

Digging Up Knowledge from Tropical Forest Floors

No one would ever imagine that digging up 50 cm into the ground could be a difficult task; it surely does not sound as impressive as climbing a 50 m tree in South American jungles or going into the depth of the ocean looking for secretive marine creatures. But I can assure you that it is somehow adventurous when you are looking for colonies of the ant Ectatomma ruidum – particularly when you are trying to collect the whole colony.

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