Bumble bee foraging paths

Bumble bee foraging paths recorded in multi-species patches of flowering plants wherein each individual plant was mapped. For each step within each path (i.e., a movement from one plant individual to another), the data file contains a separate row for each plant individual in the patch. Thus, for each step, the data represent all possible choices the foraging bee could have made, and the one choice we observed it to make.<br>Description of each column in the data set:<br>1) <b>step.no</b> - The number of each step within a foraging path at a particular site on a particular date.<br>2) <b>step</b> - The identity of each step, defined by the code assigned to the plant the bee started on and the plant the bee ended on. For example, the step "HA19HA21" indicates that the stepped occurred at site Haynes (denoted by "H") and the bee moved between Astragalus scaphoides (denoted by "A") plant numbers 19 and 21. Other site letters are "A" for site Agency and "R" for site Reservoir. Other plant species letters are "L" for Lupinus species, "P" for Penstemon albertinus, "C" for Castilleja species, and various for Unknown plant species.<br>3) <b>start</b> - The identity of the plant on which the bee started at the beginning of the step. For example, the plant "HA19" indicates that the plant was at site Haynes (denoted by "H") and it was Astragalus scaphoides (denoted by "A") plant number 19.<br>4) <b>end.plant</b> - This column gives the identity of all other plants in the patch that the bee could have visited (excluding the plant starting the particular step).<br>5) <b>used</b> - A 0 indicates that the possible step in that row was not selected by a bee. A 1 indicates the possible step that was selected by the bee.<br>6) <b>site</b> - The names of the three sites used in this study. Exact locations are available upon request from the lead author but are not provided in this data set because the focal plant species, Astragalus scaphoides, is of conservation concern.<br>7) <b>path.ID</b> - The unique path identifiers for each foraging path in the study. For example, H513P2R1O5 indicates the site (the letter "H" denotes the site Haynes; see description of the "step" column for additional codes), the date of data collection (the numbers "513" denotes May 13), the period ("P2" indicates the path was observed in the 2nd period of data collection on that day at that site), the round ("R1" indicates that the path was observed in the 1st round of data collection that season), and observation number ("O5" indicates that this was the 5th bee path observed in that sampling period; paths of non-Bombus bees are not included in this data set).<br>8) <b>end.plant.sp</b> - The species identity of the individual plant ending the step.<br>9) <b>year</b> - The year of data collection (2015 or 2016).<br>10) <b>distance</b> - The distance in meters between the start plant and each other plant individual in the patch.<br>11) <b>cos.turn</b> - The angular difference between the heading of the previous step and the heading of the next possible or observed step. Because no turning angle can be calculated for the first step in a foraging path, we substituted the average turning angle across all paths for the first turning angle in each path.<br>12) <b>constancy</b> - This column takes values of -1 or 1 where -1 indicates that the species of the ending plant of the step is different from the species of the starting plant, and 1 indicates that the two individual plants belong to the same species.<br>13) <b>uqStep</b> - A unique identifier for each possible step. This combines the "path.ID" and the "step" columns.<br>14) <b>distance_s</b> - Standardized values of the "distance" column. Values were standardized by taking the difference between each value of the "distance" column and the mean of all distances, and dividing by the standard deviation of all distances.<br>15) <b>prop_abund_all</b> - The proportion of individual flowering plants in the patch belonging to the same species as the end plant individual in each row.<br> <br><br>

本数据集记录了多物种开花植物斑块内的熊蜂（Bumble bee）觅食路径，其中每一株植物个体均已完成定位测绘。在每条路径的每一次移动步（即从一株植物移动至另一株植物）中，数据文件为斑块内的每一株植物个体单独设置一行。因此，针对每一次移动步，数据集同时记录了觅食熊蜂所有可能的选择，以及实际被观测到的那一次选择。

数据集各列说明如下：
1) **步次编号（step.no）**：指特定日期特定样地内，单条觅食路径下每一次移动步的序号。
2) **移动步标识（step）**：由蜜蜂出发植株与抵达植株的编码组合定义，用以标识该次移动步。例如，“HA19HA21”表示该移动步发生在Haynes样地（以字母“H”标识），蜜蜂在紫云黄芪（Astragalus scaphoides）的19号植株与21号植株间移动。其他样地编码包括：Agency样地（字母“A”）、Reservoir样地（字母“R”）。其他植物物种编码包括：羽扇豆属（Lupinus species，字母“L”）、阿尔伯特钓钟柳（Penstemon albertinus，字母“P”）、火焰草属（Castilleja species，字母“C”），以及以“various”标识的未知植物物种。
3) **出发植株标识（start）**：指该次移动步开始时蜜蜂所在的植株。例如，“HA19”表示该植株位于Haynes样地，为紫云黄芪（Astragalus scaphoides）的19号植株。
4) **潜在抵达植株标识（end.plant）**：该列列出了斑块内除当前出发植株外，蜜蜂所有可能造访的其他植株个体。
5) **选择标记（used）**：若该行对应的潜在移动步未被蜜蜂选中，则取值为0；若为蜜蜂实际选中的移动步，则取值为1。
6) **样地名称（site）**：本研究使用的三个样地名称。样地精确坐标可向通讯作者申请获取，由于本研究的焦点物种紫云黄芪（Astragalus scaphoides）属于受保护物种，因此数据集中未提供具体位置信息。
7) **路径唯一标识符（path.ID）**：研究中每条觅食路径的唯一标识。例如，“H513P2R1O5”的编码含义如下：首字母“H”代表Haynes样地（详见“step”列的编码说明）；数字“513”代表数据采集日期为5月13日；“P2”表示该路径在当日该样地的第2轮数据采集时段内被观测到；“R1”表示该路径在该季的第1轮数据采集中被记录；“O5”表示该采样时段内被观测到的第5条熊蜂觅食路径（本数据集未包含非熊蜂的觅食路径）。
8) **抵达植株物种标识（end.plant.sp）**：该次移动步抵达植株的物种信息。
9) **数据采集年份（year）**：数据采集的年份，取值为2015或2016。
10) **植株间距（distance）**：出发植株与该行列中其他植株个体间的距离，单位为米。
11) **转向角余弦值（cos.turn）**：指上一次移动步的行进方向与本次潜在或实际移动步的行进方向之间的角度差。由于无法计算觅食路径首次移动步的转向角，本研究将所有路径的平均转向角代入，作为每条路径首次移动步的转向角数值。
12) **物种恒定性（constancy）**：该列取值为-1或1：取值为-1时，表示该次移动步的抵达植株物种与出发植株物种不同；取值为1时，表示两次移动涉及的植株个体属于同一物种。
13) **唯一移动步标识符（uqStep）**：每个潜在移动步的唯一标识，由“path.ID”列与“step”列组合生成。
14) **标准化植株间距（distance_s）**：“distance”列的标准化数值。标准化方法为：将“distance”列的每个数值减去所有间距的平均值，再除以所有间距的标准差。
15) **物种丰度占比（prop_abund_all）**：斑块内与该行中抵达植株属于同一物种的开花植株个体占总开花植株个体的比例。