Elizabeth Schultheis

About Elizabeth Schultheis

I have always been fascinated by invasive species and their ability to outcompete native species while taking over and transforming habitats. The number of invasive species is growing year-by-year, as plants, animals, and microbes are introduced into habitats where they did not historically occur. Invasive species are often destructive, costing billions in damages to native ecosystems and human interests around the world annually. Yet, despite all the problems they cause, we still do not know what causes some species to be invasive and not others. My research addresses this question by testing whether invasive species are those that are not strongly controlled by competitors, predators, and herbivores outside their native range. That is, they are successful invaders because they have left their natural enemies behind.

Climate change – who can keep up?

Evolution has no forethought. An artic fox turns white at a particular time in winter due to the selection pressures experienced by its ancestors. This adaptation helped foxes in the past blend into the snowy background and more easily disguise themselves from prey. But what if timing of first snowfall starts to move later and later into the year or becomes more unpredictable? This is a question of phenology, the … Continue reading

What is that plant doing over there?

Why do we see a species growing on one hillside and not another? Why are some fields dominated by native plants, and others exotics? These are questions addressing the establishment of plants in different habitats, a core concept in ecology with many theories to go along with it. These theories split into a mix of those looking at (1) characteristics of the environment (extrinsic factors, like soil moisture or propagule … Continue reading

Plants fungus and insects OH MY!

Post by Zoe Getman-Pickering One of the first lessons you learn in ecology (be it a class or research) is that the natural world is infinitely complex with countless direct and indirect interactions, and it is one we ecologist repeatedly learn through our careers. I was reminded of this lesson reading the paper, “Mycorrhizal abundance affects the expression of plant resistance traits and herbivore performance” by Rachel Vannette and Mark Hunter. … Continue reading

Are invaders bigger and better in their introduced ranges?

It is hypothesized that invasive species are doing something fundamentally different in their introduced ranges – they seem to grow faster and larger, spread more aggressively, and outcompete native species, lowering biodiversity. However, these assumptions have surprisingly little evidence to back them up. In my last post, I wrote about Powell et al. 2013’s article, that found invaders may not be as bad for native biodiversity as we think. In … Continue reading

Guilty as charged? Invasive species may not be that bad for biodiversity

Invasive species are accused of being one of the major causes of modern species extinctions and biodiversity loss, on par with climate change and habitat destruction. A few charismatic examples implicate invasive predators and disease in native species extinctions. For example, the brown tree snake (Boiga irregularis), introduced to Guam in 1952, is implicated in the extinction of 9 of the 11 forest bird species, 5 of which were endemic … Continue reading

Do invasive species shift their niche to invade?

Invasive species are able to take over and vastly change the ecosystems where they invade. On par with climate change and habitat destruction, they are one of the top threats to biodiversity. A recent example in the news, Asian carp, threatens to invade the Great Lakes and decimate fish populations – this species alone could cause a $7 billion fishing industry to collapse, so we can see why it is … Continue reading