One important aspect of ethnographic fieldwork is ethnobiology: learning how humans view other living things they encounter. The ethnobiologist’s main problem is understanding the language used to describe these organisms. Imagine how calling someone a dog can be interpreted in different contexts. Between Ape and Human explores the ethnobiology of an organism that the Lio people of Flores Island (Indonesia) call lai ho’a, which Gregory Forth glosses either as “ape–man” or “hominoid.” The term has no easy translation into English, but it indicates an organism whose features seem to be a mix of humans and other primates.Forth interviewed multiple informants over several years about the lai ho’a. He describes individual informants; the nature, location, and circumstances of encounters they reported; whether this was an eyewitness or more general historical account; and the language used in describing the lai ho’a, the encounter, and its aftermath. In one chapter, Forth reviews the myths and legends of the types of beings inhabiting the Lio world. For the Lio, lai ho’a are different in kind from forest or earth spirits, “vine mothers,” and witches. For the most part, the descriptions do not ascribe any extranatural features to the lai ho’a common to descriptions of these others.The challenge for the ethnographer is to sift and winnow the content of interviews to come up with a coherent description of features for the lai ho’a. On the one hand, we look for consistencies that identify a set of features that characterize what Forth calls a zoological being. On the other hand, interviews often provide a set of standard features ascribed to a being that may or may not have been observed directly. If this sounds questionable to Western ears, imagine asking ten neighbors to describe dragons. Certain descriptions would appear in all the descriptions. This is because your neighbors are describing “what everyone knows” about dragons rather than personal observations.One of the best aspects of this book is the meticulous work that Forth did to extract a set of essential features from among all the interviews. In addition to recording the informants’ observations, he explains how he evaluated the reliability of the reports and the informants. In a final summary of the information from these interviews, Forth distills the features that appear most reliable as physical descriptions of the lai ho’a as a “zoological” entity.Some of the evidence Forth calls most reliable includes stature, posture, and facial and foot morphology that are entirely consistent with the features associated with Homo floresiensis—a species known from tools and skeletal remains on Flores Island from long before the first arrival of Homo sapiens around 50,000 years ago. However, other common elements in the report do not fit well: for example, informants commonly describe lai ho’a with a tail. And others are just in the “we don’t know” category: the extent of hair cover, the ability to vocalize, the nocturnal activity.Is it possible that the lai ho’a is a remnant or descendant of H. floresiensis? It is not out of the question, even if there is not enough biological evidence to decide. Forth is sanguine about the likelihood of a field project to find and identify the lai ho’a (pp. 238–239); it is rare to mount a field study with the express goal of locating an unknown species. However, identifying another extant hominan species would undoubtedly be a very big deal!For the general reader, there is just one important caveat to keep in mind. If Forth is correct about the relationship of the lai ho’a to Homo floresiensis, then these organisms are neither “ape-men” (typically referring to hominins emerging before genus Homo) nor “hominoids” (typically used to include species outside the branch that includes humans and the other African apes). They would be fully human, not “between ape and human,” as are all members of genus Homo.For science educators, it reveals the essence of the nature of scientific inquiry: beginning with an observation, then collecting and analyzing data to interpret the observations. It shows how Forth verified and evaluated available data. It also shows how some questions are left unanswered. Perhaps the most rewarding feature of the book is that it reveals the power of using interviews to understand ecological relationships of humans to the local ecosystems where they live. It’s messy work, but it reinforces the value of Indigenous knowledge of nature. In all, this is a remarkable and informative book that stands head and shoulders above the typical book on cryptozoology.