The context of this graph isn't entirely clear, but it's from Jeffrey Ross-Ibarra of UC Davis, and it's from a poll of 800 first year students, so I presume it's the results of a survey of their incoming class?
Maybe one of the things we need to do as part of popularizing science to the general public is to emphasize the diversity of life, and talk more about the cool things plants and bacteria and fungi and so forth do. I know I started out as a zoologist, am still mostly focused on animal development, but over the years I've become increasingly aware that there are amazing contrasts to be studied. We might wish we could study aliens from Mars, but every time I look at plant development, for instance, I feel like I'm examining extraterrestrials already.
Maybe we need to firstly educate those conducting polls of first year students, analysing and publishing the results, that this isn't the way to conduct science. Avoiding selection bias is a critical thinking skill and just one of the many pillars of scientific enquiry.
Indeed, context was limited by twitter space. A poll of students in a first-year bio class. Sent to me by a colleague at a research university (not UC Davis), with the request not to name the institution. Was not intended as a scientific analysis of student perceptions, merely a guide for the instructor to get a feel for incoming students' interests.
In the 15 August issue of SCIENCE (vol.345, no.6198), page 738 has a book review of 'The Amoeba in the Room,' in which the reviewer, Michael Shen, brings up a similar point, concluding: "Scientists are often encouraged to 'think big'. 'The Amoeba in the Room' reminds us that perhaps we would be well served to do just the opposite."