Related Experiment Video
Updated: Jan 28, 2026

New Tools to Expand Regulatory T Cells from HIV-1-infected Individuals
Published on: May 30, 2013
Evidence for the earliest hominin use of wooden handheld tools found at Marathousa 1 (Greece)
Annemieke Milks1, Maria Ntinou2, Stylianos Koutalis3
1Department of Archaeology, University of Reading, Reading RG6 6UR, United Kingdom.
Abstract:
The Middle Pleistocene (MP; ca. 774 to 129 ka) marks a critical period of human evolution, characterized by increasing behavioral complexity and the first unambiguous evidence of plant-based technologies. Despite this, direct evidence for early wooden tool use remains exceptionally rare. Here, we present the earliest handheld wooden tools, identified from secure contexts at the site of Marathousa 1, Greece, dated to ca. 430 ka (MIS12). Through a systematic morphological, microscopic, taphonomic, and taxonomic analysis of the sampled wood macroremains, two specimens were securely identified as modified by hominins: one small alder (Alnus sp.) trunk fragment bears clear working and use-wear traces consistent with a multifunctional stick likely used in digging at the paleolakeshore; and one very small willow/poplar (Salix sp./Populus sp.) artifact exhibits signs of shaping and potential use-wear. A third specimen, a large alder trunk segment, shows deep, nonanthropogenic striations interpreted here as claw marks from a large carnivoran. The wooden tools were excavated together with butchered elephant remains, small lithic artifacts and debitage, and worked bone, underscoring the diversity of engagement with a variety of different raw materials for technological purposes at Marathousa 1. These finds extend the temporal range of early wooden tools. They represent both the use of expedient larger handheld tools as well as a much smaller, likely finger-held wooden tool, which is uniquely small for the Pleistocene, expanding known functional purposes of early wood technologies. Moreover, they highlight the Megalopolis Basin's exceptional preservation conditions and its role in understanding the evolution of hominin behavior.
Related Concept Videos
The Evidence for Evolution
SN1 Reaction: Stereochemistry
In the first step of an SN1 reaction, the bond between the electrophilic carbon and the leaving group ionizes to generate the carbocation intermediate. The second step of the mechanism is the nucleophilic attack.
In the formed carbocation, the positively charged carbon is sp2 hybridized with a trigonal planar geometry. As all the three substituents lie on the same plane, a plane of symmetry for the...
SN1 Reaction: Kinetics
However, Sir Christopher Ingold and Edward D. Hughes, who studied the kinetics of various nucleophilic substitution reactions, noticed that a tertiary alkyl halide does undergo a nucleophilic substitution reaction in the presence of a weak nucleophile. While studying the substitution...
SN1 Reaction: Mechanism
Firstly, the haloalkane ionizes to generate a carbocation intermediate and a halide ion. This heterolytic cleavage is highly endothermic with large activation energy. The ionization of the substrate, facilitated by a...
Acidity of 1-Alkynes
The acidic strength of hydrocarbons follows the order: Alkynes > Alkenes > Alkanes. The strength of an acid is commonly expressed in units of pKa — the lower the pKa, the stronger the acid. Among the hydrocarbons, terminal alkynes have lower pKa values and are, therefore, more acidic. For example, the pKa values for ethane, ethene, and acetylene are 51, 44, and 25, respectively, as shown here.
Predicting Products: SN1 vs. SN2
With increased substitution on the alkyl halide,...

